Quote from Niles in Frasier's Curse
[After Niles attempts to add sugar to his coffee, but the loose lid comes off. To a pair of teenage girls laughing:] Niles: That was a very childish prank. Now you have ruined my coffee. If you can't behave like adults, you shouldn't be coming to a grown-up café. Girl: It wasn't us! [Two middle-aged men in suits start laughing at Niles]. Girl: Aren't you going to yell at them? Niles: I'm sure they've already heard me yell at you.