Im pretty sure this idea has been suggested several times in the past.
My guess is that programming the drunks behavior is not a huge deal, the problem would probably be whether the drunks would be controlled on the player side or the server side.
If the drunks are tied to players PC then you have all the lag issues of that player affecting the drunks and subsequently other players.
If they are tied to Htc servers, then it would be a drain on the system. From what I can tell, the game is designed to be as passive a system as possible on the server side to prevent such a drain.