I don't mean to hijack at all, but since we're talking about raffles, I just wanted to add my :twocents-02cents: about the subject.
I don't want to sound like a sore loser, and maybe it's since raffles do usually make more money than simply asking people to pay for things (and if that's the case, that's awesome, keep doing it), but for every winner you pull, there are probably quite a few losers. And those losers might be particularly upset if they are actually in the room for the raffle when a handful of non-regular, non-frequent tippers get their names pulled.
Just, as someone who tips regularly across the site and has also entered raffles, I've definitely felt like the tip-for-tat experience is better than raffling. That being said, I've admittedly never won anything, so yeah I'm probably sour about that. It just seems like you're making a whole lot more people unhappy than the incredible happiness to the small number who win. Is the benefit because it's a better moneymaker?
Hope that didn't sound too whiny. Sorry!