It needs to be clear if I'm shafting a sub-minimum wage worker, or declining an egregious tip-ask at the self-check counter.
Don't tip standing up. If you're ordering at a counter, that's not a tipped job. What are you even tipping for anyway? You haven't gotten your food yet, they're not bringing anything to you, it makes no sense. If the conceit of tips is that they incentivize good service, then tipping before you receive the service is nonsensical.
This culture is socially policed and has nothing to do with service, or whether tips are split, taxed, or whether that part of the country already abolished sub minimum wage