I have another event that I want to take photos of and just spoke with the owner. It is fine I can take photos. She did mention something about a photo release. It seems like this should be part of the show brochure so they know there will be a photographer on site taking photos.
These photo releases don't seem to be so much about someone giving you permission to take their photo as much as it is a release of liability for the photographer if someone in this "everything is on the internet" age gets a hold of a copyrighted photo and without the photographers permission uses the photo inappropriately somehow. The release that is signed keeps the photographer from being liable in a case like that. As I read it,
I have the rights to the photos and to use them in a non commercial fashion, for my own
business promotions, sales, fine art, etc.