I think that if you needed a drug to socialise at all, whether it be alcohol, beta-blockers or xanax, then you have a problem, that problem being social anxiety, and using alcohol to 'feel normal' is definitely a road that leads to drug abuse, namely alcoholism. I think that people definitely do self-treat social anxiety with alcohol and cause a problem that way.

However, using a moderate dose of alcohol as a one-time thing to lower your inhibitions for socialising with strangers, where there is no social penalty for drinking, is no worse than taking beta-blockers before giving a public speech.

It's not 'dependence', it's an aid. Dependency is needing a drug to function normally all the time, not in a novel and stressful situation. If you're using alcohol every time you meet new people, then yes, you're on the road to dependency and eventually full-blown alcoholism. The next time you're trolling for social contacts, you shouldn't need alcohol to 'loosen up' as you've already been in that situation and should have learned how it goes.

But for this, whatever you need to be comfortable might well involve taking alcohol. On the other hand, if you've not drunk before then alcohol might be a terrible idea as it's easy to take too much, and if you're driving then it's a terrible idea as well because drinking and driving is really, really stupid as well as being socially unacceptable.

People use drugs all the time to alter their brain chemistry. The most common one is caffeine, used to increase alertness and mental clarity. Dependence on the drug caffeine to be normal is very, very common. Alcohol dependence is less common and physically more dangerous, hence your likely alarm at what seems like the first step on the road to ruin, but it's not inevitable or even likely as a consequence of having a moderate dose as a one-time thing.