It is mainly a US thing, and then varying by the occupation. Some prominent restaurant groups have tried a "no tips" policy, combined with higher wages and either a surcharge or simply tucking the difference into their prices, as well as paying the back staff (cooks, etc.) more to put them on a par with the front staff. About the only common result has been a lot of argument and disagreement--from everyone. Customers, workers, trade
groups, no one has come out with a real answer as to what is "fair" much less "best".
boatpoker, if it is mandatory, that's a service
fee--not tipping. Yes, that's gone to court in the US as well.
We are seeing a surge in home delivery
of groceries in the US now, after some 10-25 years of startups trying to do that with varying success. Amazon Prime Now quietly inserts a "suggested" tip for every order that supposedly goes to the actual picker/delivery person. But they do say "suggested" and you can easily adjust that.
InstaCart (who serve many companies) adds a tip, but apparently their tip is a weasel job. The "tip" is to support InstaCart itself, not the folks filling the orders!
Having grown up with the system I can certainly understand what is expected under it, but when I see a tip jar for something like...a counter clerk pouring my coffee? Someone handing me a slice of pizza? It simply has gone absurd in the US in the last ten years. Folks deserve a living wage, and too many weasels have used tipping as an excuse to screw their staff, for too long.