I find it delightful, frankly. I don't like taking things so seriously all the time, and I like finding humor wherever possible. The problem is that not everyone is self-deprecating, so they don't take it well if you poke as much fun at them as you would and do at yourself. Their pride and resentments kinda wreck the whole thing, and then you have someone who is now even more disagreeable on your hands instead of lightening the conversation a little.
It's frustrating really. It's why I appreciate people who are not so up tight that they can't take a light-hearted joke now and then at their expense. Certainly when sarcasm is used with cruelty - biting sarcasm that has a nasty spirit to it - that can in no way be excused, and unfortunately that's the brand I see used more often than the former. But I love talking things over - anything really - with a good friend who will make fun of me and allow me to make fun of them. Most subjects bore me. If you can inject a little humor, the conversation gets more interesting. We're humans for heaven's sakes. Anyone who thinks we are somehow perfect is... well, an idiot, Lol. But I mean that in the best way possible.