People that work at restaurants, what was your worst experience with a customer?

It was years ago when I was waiting tables, but I worked at a sushi restaurant and in walks this woman with a large purse. When her food arrives, she produces a big green squeeze bottle from the purse and proceeds to squirt some sort of super pungent green sauce over everything. Like we're talking right on the sushi!

I was actually inwardly a little amused by the whole thing and was speculating what it might be? She looked vaguely south asian? Anyway, I quickly realized the smell was going to bother other customers, so I politely asked if she might move to another table. It's not one I usually gave to customers as it was near the kitchen with servers going back and forth a lot, but it was far enough away from the main dining area to keep the smell localized.

Well, then she blew up. Omg. I eventually had to call the manager who tried to talk to her in calming tones but with little success. And it fell on me again to escort her out. (I'm a pretty big guy, though kind of baby-faced and not very intimidating, but the manager was a small woman and I guess I was her best option?)

As I led her out, she started bitching that we shouldn't use disposable chopsticks. I think she was just venting about anything at this point? I said well, bamboo is still a lot better than plastics. I told her if she wants a fresh pair to take home, she could have it. This seemed to catch her off guard and she accepted the chopsticks. I think somehow this was a "win" in her mind and she left with a smug expression. Never saw her again, thankfully.