Despite Earl's mother's remark, alcohol is even more addictive than cannabis and of course also fosters antisocial and even aggressive behavior.
Despite what Joy says, pregnant women should drink no alcohol at all, not even flavored vodka.
While it is in character for Joy, Earl and Randy to spread medical misinformation, drinking alcohol does in fact also kill brain cells, same as smoking pot, especially in such regular heavy drinkers as pre-list "bad" Earl and Randy. Also, humans only have one single liver, not two.