I think it's a problem of adjusting to something new.

Looking at alcohol for comparison, societies have evolved cultural norms for dealing with it. In W. Europe for example, wine is part of meals; in UK a pint at the pub is a routine social occasion. In the US, with the heritage of puritans, "reformers" and a younger culture, there is more of an "all or nothing" mentality, the prohibition experiment, and youth drinking to get drunk.

As cannabis legalization spreads, norms will develop to govern what's acceptable in households, coffeeshops, etc.