“When first introduced, the ban caused much controversy and some open defiance. Some people took the trouble of travelling to neighbouring Johor Bahru, Malaysia, to purchase chewing gum. Offenders were publicly "named and shamed" by the government, to serve as a deterrent to other would-be smugglers.”
Asia has/had a TB problem and spitting in close quarters spreads it and it takes a really long time to incubate. There is a cure, but the protocol is very strict because the TB bacteria is good at hiding. You could be exposed and get sick years later.
Reads like a fever dream.