In one episode of Hey Arnold, Helga wins a free dinner at a fancy restaurant, but after (or is it during?) their meal she finds out that she went to the wrong restaurant, and ends up getting out of it (before Arnold convinces her otherwise) by calling Nadine and asking her to infest the restaurant with her bugs. When she does, a cop or health inspector tells her "if I were you, I wouldn't pay my bill."
Now, in real life, if a restaurant got shut down while customers were eating, would they be excused from paying for their meals? Ditto for if the place catches fire before a customer can pay.