One solution would be to pay at the time that you order, but then I’d be horrified at the concept of being asked to tip BEFORE your meal, in which case tipping switches from being mild/borderline extortion to being full-on blatant extortion. So, credit card for deposit would be better, like someone else suggested.
Or, if the point of this isn’t to ask for solutions but to complain about ‘people getting worse’… There’s always been shit-heads and there’s always going to be shit-heads out there. Maybe the percentages are shifting, but if so it’s likely the not-so-new problem of cities growing bigger and feeling less like a community, and if someone doesn’t feel like they have any connection or responsibility to the people that live around them, then this and countless other crimes and social breakdown tend to result. Maybe the nature of the internet and media etc. is making that worse, but if so it’s still only a different flavour to the old and ongoing task of maintaining social cohesion one generation to the next. I admit, some days I almost want to lose faith in that, but it’s gonna take more than an increase in petty theft to do it today.