Well, yea, having too much build up / skin on your lips makes kissing not so much fun.. We just kiss very gently (no rough tongue kissing action :-)).
My wife and I just came home from a restaurant where we had breakfast. Just like most/many, many other things, it's way less fun with EC, but it was ok. Not terrible. But I don't have huge crusts on my lips anymore because I've stopped leaving them alone. I didn't really go to restaurants when I had big yellow crusts on them (so about half a year).