Chuck's Beer Cozy

Chuck - my ARMY hubby (who is training to be a Drill Sergeant) LOVES beer. He almost ALWAYS uses some sort of Cozy for his beer when he drinks. I've been so into knitting lately, I thought I'd knit him a cozy for his beer.
After one failed attempt, I came up with this one... but, he doesn't like it all that much, b/c there isn't a bottom to it, and he says it keeps falling out of the bottom... UGH. I'll have to come up with something else.