The "respect" avenue was more there because she was a "chef", or called herself a "chef." If food prep is your calling, I would think you might try to at least respect your craft and the face you put on it for your customers, even if you don't respect the customers themselves.
But yeah, I've been witness to, and have been with as part of my party, people who can't seem to hold their tongue and blurt out some of the most condescending, unnecessary nonsense to wait-staff.
My brother-in-law once called our waitress over to complain that his burger did not having pickles on it, stating that the menu said right on it that the burger had pickles. He wouldn't drop it through the whole meal, and kept talking about it loud enough for people to hear. On the way out I grabbed a menu just to see, and listed was "pickled onions"... not pickles.
My dad is also ridiculously particular, and for a few years he had picked up this completely dumb saying from some movie he thought was especially clever - "Did I stutter?". So, when someone would ask him to repeat himself, or explain something again he would usually offer it as an aside, hypothetical response - like something he "should have said." The first time he actually used it on a waiter at a Chinese restaurant we were at as a family had us all intervening to stop him and apologize to the waiter - especially considering that it was obvious English wasn't his first language, and he likely had zero idea what my dad was even trying to convey.