Why Do They Call It Bluesfest?!?!?!?!?!?

Over the weekend a big gust of wind blew over the mainstage at the Ottawa Bluesfest.  It was while Cheap Trick was playing.   According to this article (click HERE) no one was hurt.  I must admit that when I first read Cheap Trick playing at a blues festival I was a little taken aback, then I looked at the whole festival list. I must admit it is huge, but the majority of the performers are not blues.  Take a look here for the full list of performers.  In fact if you read this article about the festival you wouldn't know it was a blues festival.  You wouldn't even know that BUDDY GUY was playing!!!!  I know the blues are hurting, but if you are going to have a blues festival wouldn't you have blues bands?????  If you know the answer to this perplexing question please let me know.