Back in the days of yore it had a huge impact. My personal eperience is that nearly everyone was off their rocker on something or other. There was very little, if any, booze in them days. Let's not forget the baribiturate brigade as well - plenty of them in those days too - something I could never quite get my head round.
Times have changed. Booze plays a bigger part these days - with late bars at most places - as Tabs said. There are still plenty who like their comestibles - but it ain 't like it used to be. Neither is the gear for that matter!