That's one important reason, but there's another one that is even more neglected: it just... tastes good (for those of us who like it, of course).

For example, as a 90 kg man, for me drinking a single 33cl bottle of beer has pretty much the same effect as drinking water, i.e., I don't feel anything at all (note that I don't drive, in that context it would probably still be relevant). So when I have a single beer with dinner, there is zero intention of socializing, stupefying myself or whatever. I just like the taste (and don't order alcohol-free beer, which is healthier, because I hate its taste).

Similarly, having a red wine with a strong sheep milk cheese is an amazing experience, just because the tastes combine so well and enhance each other.

If there were alcohol-free versions of the beverages that tasted the same, I'd probably use them most of the time (except in some social contexts). There is no such thing, though.