I have before, and it's quite enjoyable. In fact, I'll agree with air, on longer rides I like an actual meal during the break as rabbit food does not suffice. However..

..I'll not ride and have beer again until I can learn how to ride like a normal person. Last week I rode to the bar for a burger and a couple Boulevards. On the way home, I decided to hammer the MTB up the hills.

Yes, I saw my dinner and beer again. I guess it was a good thing, in that none of it got absorbed, right?