There is not a single reason for any human to get access to alcohol to drink.
Edit 1:
Just to add the people who say that banning does not work is like saying banning guns does not work because people is going to find a way to get them or like saying we should not have speed limits because it does not prevent people from speeding. (Their opinions does not make sense to me)
Whether or not you think that, actually enforcing a ban has proved very difficult in the past. Better resources for addicts of all nature is proven to be much more effective than outright banning things.