Rock and roll baby!!  Some people can do it, and others just shouldn't.  If you can't handle your alcohol, probably best to stay away from it...especially if you're working.  I get it.  Being a drummer in a band is fun.  But I'm going to guess that if he keeps this up, he won't be a drummer in a band for very long.  Congratulations to whoever hired this guy at their wedding.  You just hired the world's drunkest drummer.