Dirty? Geez, have you been to BOS lately?

I don't think MSY is dirty (it is my home airport), and I think it's definitely improved over the past two years with many renovations and the opening of the new C and D concourses.

I have never seen the airport "zoo" like, even during Sugar Bowl, Super Bowl, or Mardi Gras weekends, probably partly because it is way too big (only about half of the 40 or so gates are in use at this time).