Dude, I would have been so pissed.
Wow wow. Having been a wedding DJ a few times for friends (because I have PA and an extensive catalog of songs on file...not because I'm a real DJ lol), I know it's definitely not one's role to hog the spotlight...quite the opposite, rather.
Provide the soundtrack for their special day, do what they're paying you to do, and provide services fulfilling what was agreed upon doing beforehand...shouldn't be a big deal.
Some people just don't get it.
Yeah, that part really got me. If I misquote a client and don't figure it out until they've already paid off their contract, I'm just going to have to eat my mistake. I wouldn't dare go back with my hand out for more!