Before we go on about meting out penalties for not returning trays, please pass a law clarifying that one has to do so after eating (Time to penalise those not returning trays at food centres, by Mr Ang Tun Loon, Sept 22)
Without a clear ruling, please don't expect the general public to be civic minded.
Right now it is sort of "up to you" because there isn't a clear mandate. Make it clear and we as a society will adhere to the law.
Ong Hock Cheng