It's not nearly as prevalent as "hay guyz i hav to go aftr i lvl k?" - which seems to be an NA thing. Still, it happens to me often enough to be noticed. On a side note, I think any parties I make from now on, I'm gonna kick on the spot, anyone who says they need to leave after they level. Because we all know "need to leave" really means "don't want to stay", and if said person is so busy, s/he should get a head start on that incredibly important task instead of exping anyway.