Speaking from experience, I don't think they feel irritated at all.

I've been drunk quite a few times and I can comfortably tell you that there's nothing and I mean nothing that could irritate you when you're drunk. There's a kind of euphoric feeling that you get when the "buzz" as my friends like to call it, hits you. At that point everything from the way you walk to the way your nose looks in front of your face will fascinate you.

Most times, people that are drunk aren't even coherent enough to allow their brains process what might irritate them and what might not because your brain is basically shutting down. I've never felt irritated by anything while I was drunk and I'm one of those people who remember every single detail about being drunk, including all the embarrassing things I did when I was less than sober.