I just bought the beer and the whisky. I was wondering, what other benefits are there from buying the beer? It has the same stats as Shadow Mane, except that it makes them burp after drinking a potion...is that it? I like the game, and I have no problem supporting development, but is there another benefit to the burp?

Absolutely no benefit to any of the three, they're just aesthetics. It's just a nice way to say "thanks" to Andy is all.