"Compared to..."
Maat
It's the "compared to" in your post that's the issue. It's not either/or, is it? A compelling reason for having a drink during a duty cycle is to help get to sleep in a noisy hotel, at the wrong time of day, when there's only 8 1/2 hours to get 8 hours of sleep, on the wrong time zone....
If it was a simple choice - pilot over the alcohol limit, or pilot who's not had enough rest - it would be easier to make a judgement. But it's not - the true problem is "pilot who's not had enough rest, and has had a couple of drinks to try to alleviate that."
R