I know it’s a zombie, but I honestly have not noticed the liquid used imparting any flavors to the chicken itself. To me, it’s just getting the chicken off the grate and relatively eating all around, and the evaporating liquid to heat the interior. Water works just as well in my experience.
I like to use a pineapple and cook the chicken beer can style. Just trim down the pineapple until it fits inside the chicken (leaving the base alone so it can act as a stand) and stick on the grill. As a bonus you can use the trimmings from the pineapple to make a pineapple salsa to have with the chicken.
As a note: unlike with the beer there is a slight flavouring of pineapple in the finished chicken.
Cooking For Engineers agrees with you
It’s interesting, though, as the comments seem to disagree with the engineer’s assertion. I could see the beer flavoring maybe part of the breast that is closest to the inside cavity, but I can’t really see it flavoring anything else. Like I said, in my experience, I didn’t notice any difference, and I used a stronger beer, heavier beer (which is what the comments say to use.) Personally, I find a properly, normally grilled chicken as good, if not better, as it’s easier to maneuver during grilling if necessary than something with a big hot can of beer in its bum. But grilling and barbecue is made for these sorts of debates and arguments. 
You can also use a can of hard cider, it puts a really a nice flavour in the chicken, especially with rosemary and thyme sprigs…
And it’s beer butt chicken! Rude,crude and delicious!
Pabst Ass Fowl perhaps?
Meathead also agrees. Beer can chicken is a waste of a beer and potentially dangerous too. Vertical roasters are cheap. Get one that promotes air flow.
The zombieness explains why I didn’t recognize any of the names.
But since we’re here: would this be a bad idea wit a beer can with a widget? I imagine the plastic will do badly on the grill.
Thanks for that. Excellent information. I have in fact tried this once and the chicken turned out great. I guess it would have turned out great regardless of the beer can.
Woa, blast from the past. I did remember starting this thread, and it’s already been TEN YEARS!
Gosh.
And I still hate beer.
Beer contains glutimates, and if you like that flavour (as most people do), used in moderation it will make almost anything taste better. But since that’s the same flavor as chicken stock cubes, I wouldn’t think it would make much difference to chicken. I’m thinking that the “water will work just as well” people are probably right.
Whuh? Go to an Asian market- you can buy them in huge quantities for nothing. Or, you can go somewhere like Penzeys and get 3/4 cup for like $9.
The govt. stopped the ban in 2005, so they’re pretty common now.
Some people are hopeless. 
Not in Jan. 2005 when the post was made. 