Bit of both - most people adapt to the taste, not drinking cheap rot also helps. Also yeah a lot of people like having a buzz or the adventure of getting proper wrecked once in a while.
We're even worse with caffeine tbh, first thing in the morning for many and no laws to say you can't chug a litre of espresso then drive a car shrug, take out a can of beer at work and many would still raise an eyebrow or object but they won't bat an eyelid at a can of Monster/Rockstar etc, no matter how much of a jittery irritable loose bowelled mess it makes you..