Addendum.

Customers who are self-consciously spontaneous and casual are the worst.

They think that they're cool with everything and the lack of rigidity is easy on you, but it actually takes more time and they have higher expectations, in addition to them having a repulsively higher self-image from being "cool" and "low-key" and "not one of those customers."

Like, they'll think that they can just grab you and tell you something and get you to do it right away, or call out to you, and it just ends up being them doing whatever they want whenever they want, and it's almost like you're their servant rather than them being customers who are given moments of carefully-created space in which they articulate their needs and you meet them, like, it's actually those customers who you see looking and waiting for you if they happen to need something when you're not over by them.

The grabbing chairs from another table is a big "tell" -- who does that at a restaurant, except for someone who's entitled?

And trying to help you out by mopping up shit with napkins is nice on the surface, but actually more symptomatic of their general obliviousness and lack of self-awareness. 

A thread throughout all of this is non-recognition of social boundaries with space -- with chairs that the restaurant moves but not you, with the waiter being at a distance and there's invisible walls where you should not call out, with the waiter as someone who creates narrow spaces of exchange along set patterns and comes into it so you can interact with them, rather than you initiating it wherever and however you want.