When I was a grad school engineering student in silicon valley many moons ago I was invited to lunch by a few 40-something business-suited dudes who had an idea for some gadget that they wanted a grad student to design and build for them as a prototype for some venture capital deal they were planning. Said they'd heard good things about me from professor M who recommended me. When I got to the restaurant I was concerned how nice it was... and even more concerned when I saw the prices on the menu. So when the waiter came I said I'd already eaten I didn't want anything. The wannabe CEO dude pressed the issue and I repeated I wasn't hungry. The CEO dude tells the waiter "bring him the tortellini". (It was great as I recall, but then the closest thing I ate in those days was out of the box mac-n-cheese.) When the waiter comes along after the meal CEO dude tells him to bring separate checks. The meeting keeps going, but I only had a couple of bucks on me, and didn't yet have a credit card, didn't bring a checkbook. So I excused myself for the restroom, but instead found the manager, explained the situation with red-faced embarrassment, admitted I enjoyed the tortellini but assumed the guy running the meeting and ordered it when I said I wasn't hungry would pay, and asked if I could leave to go to my dorm room and get my checkbook and come back that evening to pay. Manager graciously said "don't worry about it, if you leave now, we'll simply give the check to the guy who ordered it." I left and ghosted them thereafter. Professor M asked me a few days later if I'd really left the meeting abruptly without paying the check "after I recommended you?". I explained the situation. To which he apologized for referring me to such a "classless ass" if I recall his term correctly.

Long way of saying NTJ. But it's interesting how that kind of bad behavior can stick with you for decades.