General question about alcoholics.

Edit: most of yall are saying this is from the person being already drunk everyday, which makes more sense than my theory. Thanks for your responses.

This is something I'm just curious about, not trying to sound judgy as I have my own problems.

Has anybody noticed that alcoholics tend to get sloppy drunk easier than most, even with a tolerance. I'm talking about that friend that has 3 drinks and gets mean, cringe, embarrassing or completely uninhibited and ultimately becomes an alcoholic. It's almost like they metabolize it differently or something, like how some Native Americans get after a small amount of alcohol.

Thoughts? Thanks!