They tend to devolve into awkward situations for people like myself who don't drink or don't want to waste time with the "oh really? you don't drink at all?" conversations. I'm not an alcoholic, but people consistently feel the need to dive into why I don't drink, choose not to, and have never had a drink.
And as much as people here or anywhere may say that they either A) don't care whether I'm drinking or B) feel awkward around others who don't drink, the reality is that the culture is centred around whether you drink and how much.