Buy one of these pens for $15 and receive a "free" video game.
Just put the gold coin donation down for the beer snacks
The trouble with that is that people think they've found the holy grail, the clever loophole that somehow renders them untouchable by a foolish beaurocracy. It just doesn't work that way - they are the oldest tricks in the book and totally illegal (many are even mentioned in the very laws they try to circumvent). Sadly there are few situations where you can walk away unharassed on technicalities like that.
In the UK where the weekend licensing hours were so messed up, we used to have all sorts of pubs and clubs that would try the following tricks:
Selling raffle tickets where 'everyone wins a prize' (a beer);
Selling a crappy overpriced plate of food on entry and claiming they are a restaurant (and therefore entitled to more relaxed licensing hours);
Claiming the beer was a free gift but you were hiring their glassware etc etc etc.
As far as I know they all eventually got shut down and prosecuted, because the law looked at the end result and how the 'reasonable man' saw it, not how the perpetrator wanted to portray it.
I'm not a legal expert here, but my gut tells me to tread carefully on this subject. The trouble is that the people who have the liquor licences can be very persuasive with the offices that control the licenses, and if a licensee is getting upset by a potential threat (ie, people drinking elsewhere and not in their venues) then things can get a bit ugly. I'm sure it is fine to have club money going into buying beers for members, but when you start to talk about 'entry fees' or 'donations' at events where alcohol is being served the powers-that-be can see through it all like glass, and they are probably just best left unmentioned.
There's also the 'responsible service' issue, ie if someone gets themselves in trouble through excess alcohol consumption it can all get a bit messy as to who is liable. It's a miserable state of affairs that it can come to that, but it's a factor to consider if you plan on making alcohol available to people that aren't close friends.