alcohol use stunts muscle growth because it screws with anabolism.
6 pints of beer a day is NOT moderation. Hell it boarders on a drinking problem if you ask me, but I'm not here to judge. I like my beer...Hell I make my own beer!
But I drink one or two pints, or a kolsch glass at most on the days I drink.
Alcohol aside, that much beer/cider means a TON of empty calories from alcohol and residual sugars, which is going to make balancing your dietary needs a bit of a pain.
You have to decide if 6 pints (3 quarters of a gallon PER DAY) is more important than the physical changes you want to see in your body. And again...long term health, liver damage...etc etc.
/soapbox