Avoid it at all cost...unless you have never seen the greasy pole contest....the food is not anything to speak of other than standard vendor fare and the restaurants are generally jam packed with drunken revelers. Even if you never have been and you got the itch, you'd be better off looking for somewhere else to enjoy a meal, at least the weekend of Fiesta.
I went 2 years ago. Don't really recall that it was too much about the chow. There are vendors set up that sell Italian cookies and sweets, also some pizza slices and maybe a sausage guy. More like carnival food, fried dough & cotton candy.
A great place for a cannoli on any day (not just Fiesta) is Caffe Sicilia on 40 Main St.