for the average person beer would be the safest and cheapest thing they could drink. In crowded cities and towns water was rarely safe because of open sewers in the street and little to no awareness of sanitation and the spread of disease. milk would have been expensive for people who didn't have a cow of their own and wine was for the wealthy and the aristocracy. this left the average person with pretty much one option. People would drink beer, or ale, with meals and maybe a few extra glasses here and there, but it wasn't about getting drunk, so much as it was getting fluids. no doubt there were alcoholics, but beer wasn't seen the same way then as it is today. that was just what you drank when you were thirsty. parents would give young kids weak beer with their meals and everything. people might have had a little buzz going most of the day, but getting drunk in your day to day life was never socially acceptable.

of course if you look up the gin craze in England you'll see some pretty hardcore alcoholism running rampant in the population, particularity London. worth a wiki if you're interested