Actually, they don't. In western countries they're not teetotalers (especially the younger set). But as a group they do not buy or drink as much alcohol as non-Muslims.
Not even close.
Drinkers tend to think all non-drinkers drink "in private." That's not an accurate judgment.
Wow, I have never heard that one---that all drinkers tend to think all non-drinkers drink "in private." News to me!
Anyway, I can assure you that I, at least, have never thought that. Rather I have always thought that most non-drinkers were . . . non-drinkers.
However, I was stationed in the Middle East once and was privy to much of its private culture. I guess b/c drinking was so socially inappropriate, I only saw drinking in private. By private I mean at private parties, even if many other people including Americans were present; in private dinner rooms in all the international hotels, etc.
It was far from a teetotaller culture. It wasn't uncommon at all for Americans to be asked over for drinks.