There's a joke that if something isn't nailed down, it'll be stolen. Whereas in some countries the crime rate is so low you can leave your bag somewhere and come back days later and it will still be there.
People here in Singapore sometimes leave their wallets or phones on tables in food courts to reserve them. Unlocked bikes don't get stolen, either.
(Our police here in Singapore sometimes runs awareness campaigns on pickpocketing with the slogan "low crime doesn't mean no crime" to get people to watch out. It's not really necessary, though.)
When I was in Chiang Mai in Thailand last year, the locals also left stuff around and didn't seem particularly worried about petty theft.