a publicity stunt isn't a bad thing, TechCrunch gives a lot of smart people building cool stuff exposure and this is free marketing for them. What's wrong with that?
I think it's the most fun way to do a short event like that, I don't think anyone assumes more would get done in 24 hours than in 4 6 hour sessions.
Haven't done one of these before but when I was doing uni programming project we would always end up having a lot more fun with it pulling a big night than just running normal uni hours.
I think what these people did all night was really cool; if I wasn't so busy I'd almost consider giving it a try myself sometime.
But please don't think that this was anything more than a publicity stunt and whatever you do, please don't call them "hacker gladiators".