I'm not sure how the offical campgrounds (parks and KOA's, etc) did. I don't think they got a lot of business especially if they were off the main evacuation routes. Plus, it was over 100F and a hurricane was coming. Not the best time to be in a tent. <img src="/images/graemlins/shocked.gif" alt="" />
However, a lot of people were sleeping in their cars in parking lots, fields and alongside the road. I suspect most didn't have any camping gear, didn't know where campgrounds were, or the whole idea of camping was so foreign to them that it never even occurred to them to look for a spot.
-Blast