On a recent sunny morning outside Bangkok's Grand Palace, a shop selling mini pineapples is doing a roaring trade. Hordes of parched tourists, nudged along by tour leaders, shuffle along the sidewalks with the northern Thai delicacy perched on a stick.

The visitors' bright red and orange attire contrasts sharply with the black worn by queues of mourners streaming past them to pay their respects to the late King Bhumibol Adulyadej, who died on Oct 13.

Mourners and tourists enter the same compound seamlessly via different gates, reflecting the pragmatic attitude that keeps the kingdom's lucrative tourism industry humming along amid its trials and tribulations.

According to a report in November by Siam Commercial Bank's (SCB) Economic Intelligence Centre, tourists spent 1.46 trillion baht (S$58.6 billion) in 2015 and the sector accounted for about 11 per cent of Thailand's gross domestic pro- duct (GDP).

Tourism, the report said, "now rivals manufacturing in economic importance to Thailand".

Even as manufactured exports slumped, the "export" of services - mainly tourism - helped push GDP growth to 2.8 per cent, it said.

Strict laws against comments insulting the monarchy mean few dared openly discuss their initial fears for the industry when the government declared a year of mourning after King Bhumibol's death.

Many nightlife outlets in the country shuttered or went silent after the government asked people to refrain from entertainment for 30 days.

But two months on, the show has gone on, albeit with some tweaks.

Usually scantily clad models covered up with long-sleeved dresses that went down to their ankles at the annual Motor Expo last month, for example. And there were noticeably fewer New Year countdown parties, even though Christmas trees were lit up in public spaces and carols were heard in department stores.

Amid these adjustments, Thailand welcomed its record 30 millionth visitor last year on Dec 5. Fittingly, she came from China, the biggest source of tourists to Thailand.

Ms Huang Junyi, from Guang- zhou, won plane tickets to Thailand, a stay in a luxury hotel and a mobile phone with a SIM card.

"The tourism industry is a source of livelihood for millions of Thais," said Mr Chattan Kunjara na Ayudhya, deputy governor for marketing communications at the Tourism Authority of Thailand. "Whatever happens, it hurts, it has negative impact... but we need to move on. We can't let these things deter us from moving forward."

TEFLON TOURISM

Indeed, the tourism industry has exhibited a Teflon-like quality amid political turbulence in the past decade.

Visitor numbers continued climbing in 2006 after then prime minister Thaksin Shinawatra was ousted in a military coup following street protests.

Travellers were scared off after political factions seeking to oust the then Thaksin-aligned premier Somchai Wongsawat shut down Suvarnabhumi Airport in 2008.

But they were not afraid for long. In 2010, visitor numbers grew 12.6 per cent.

That same year, Thaksin supporters occupied downtown Bangkok, sparking a military crackdown that left more than 90 people dead.

It did not stop visitor numbers from climbing 20 per cent in 2011.

This pattern was repeated during the most recent coup in May 2014: Visitor numbers softened by 6.5 per cent amid street unrest, but rebounded by 20.6 per cent the following year.

Bombs do not seem to have a lasting effect on Thai tourism either.

On a year-on-year basis, visitor numbers kept growing - albeit slower - in August 2015 after a massive bomb went off at the popular Erawan Shrine in downtown Bangkok, killing 20 people, mostly foreigners, including one Singaporean.

In August last year, when improvised explosive devices killed four people and injured dozens across seven southern provinces, including key seaside tourist destinations Hua Hin and Phuket, year-on-year figures continued climbing.

"There was some impact, but not much," Ms Pratuang Wantam, manager of Baan Nilrath Hotel near one of the blast sites in Hua Hin, told The Straits Times. "I think the worsening global economy has had a greater impact on my business."

Part of the reason, she said, was ramped-up police presence in key tourist destinations immediately after the blasts to reassure tourists.

At the same time - and partly for political reasons - the authorities have consistently shied away from labelling these incidents as terrorist attacks.

The Erawan Shrine bombing was attributed to human smuggling networks thwarted by Thai policing, for example.

TOURIST MAGNET

For many tourists like Ms Shao Hua, a 24-year-old interior designer from the northern Chinese city of Dalian, Thailand is perfect for a maiden foray into South-east Asia.

"It's got the beaches and it's got the cities," she said. "I love tropical fruits, they are so sweet. And the shopping - I can't control myself!"

Mr Mariusz Kwiatkowski from Poland said he decided to take his family to Thailand after hearing from other travellers in Europe about how it is a safe place for families.

"The country is really interesting, especially if you are European," he said while waiting to board a train to the northern city of Chiang Mai.

The resilience of Thailand's tourism sector has drawn Singaporean investors.

In March last year, Singapore hotel chain Clover opened a 95-room outlet in Bangkok's Asoke district. The whimsical hotel, with artwork of wildlife on its walls and ceilings, reported an occupancy rate of 90 to 95 per cent in November and December.

The company is renovating a property in Pattaya to turn it into a hotel by next year. "The clientele in Pattaya is changing," said Dr Lee Soon Tai, chairman of Hotel Clover group. While the town has been a haunt for Russian visitors seeking escape from frigid temperatures at home, he said, it is now attracting more tourists from the growing China and Asean markets.

CLOUDS ON HORIZON

But the industry is facing challenges too. Last year, the authorities cracked down on "zero-dollar tour" companies, which charge Chinese tourists little upfront but ferry them to overpriced restaurants and shops to make up for the difference.

Tour bookings fell as pricesrose relative to other destinations.

The tourism authority's Mr Chattan expects the effect to be temporary. "You have surgery to fix an ailment within you," he said. "The scar will hurt for a period of time… In the end you will be well."

If the Thai government had let the problem fester, "who knows, the Chinese government might one day tell its citizens 'don't come to Thailand. When you come you will be cheated'," he said.

Then there are longer-term issues. Despite increasing numbers of tourists, the average amount each one is spending has been shrinking because visitors are shortening their stays, noted the SCB report.

"The increase in average spending per day does not compensate for the briefer duration," the SCB report said. In 2015, each visitor stayed an average of nine to 10 days.

Meanwhile, tourist crowds are straining Thailand's famed natural attractions. National park authorities had to close Koh Tachai, a popular island in the Andaman Sea, last year to allow the island and surrounding coral reef to recover from environmental damage.

The "key challenge is how Thailand will enhance any other areas of tourism and continue infrastructure expansion to accommodate an increasing number of tourists", said the SCB Economic Intelligence Centre.

Suvarnabhumi Airport, for example, received more than 50 million travellers in 2015 when it was built to handle 45 million. Expanded facilities are expected to come onstream only in 2019.

Having attracted record numbers of holidaymakers, say experts, the authorities now have to focus on accommodating them sustainably - while enticing them to stay longer.