I'm far from a historian or anything like that, I just find history to be very intresting. That being said, my understanding might not be 100% accurate so I'd love some insight.
So, I believe I read or heard somewhere that because water purification techniques weren't very great back then (I'm thinking medieval times, although I've read that workers in a brewery in England avoided getting cholera because they drank beer instead of water from the wells) most people drank beer/ale or wine because it was safer.
If this is true, how were people able to function drinking alcoholic beverages all day? I assume they aren't as strong as today, but still. Additionally, how common were liver problems and addictions due to alcohol? Were there any rehab type of treatments for people who drank too much, or did they just die?
This is a common assumption but has very little evidence to support it. It has become one of those "truisms" that keep living because they are such great "party facts" for the historically inept. This, this and this offer variants of the question and feature answers you might find informative (previous r/AskHistorians threads). The simple (and probably inadequate), answer is that people did drink water, had relatively little trouble with finding fresh water, and that people generally did not drink alcoholic beverages all the time.
That being said, history did have its drunkards, big and small.