Sorry that happened, though can't say I'm surprised to hear it happens more frequently than that one-off example. I feel like it must be common anywhere there's an intersection between low economic opportunity and sanctimonious Christian smugness.

They probably think it's like a cheat code to avoid paying while still somehow earning more good boy points with god.

(Not to say I'm a fan of tip culture either, but that's how waitstaff get paid in the US, and stiffing one person on a tip isn't going to change that.)