I'm pretty sure that shuttle is free from the fairgrounds. If it is where I think it is, it is grass as well. I had grass down in Aimes a couple years ago and I think it is the only way to go on a nice day like that was.
Sally's is a bar. I've picked up from this thread that Sally's will be where the NDSU party is for people who don't want to deal with the tailgating situation.
I for one don't mind the fairground option because with the game and transit being almost 4 hours and they letting you have 4 hours after the game it will be a lot of fun and you can find someone to sober up over the course of almost 8 hours.