I volunteered this year, it was a pre-con shift on Wednesday and it was weird.
I got an email saying my assignment was 1:30 at Town and Country. I got there at 1:15 with a bunch of other people and the guy was clueless, said none of us were supposed to be there. We showed him our emails. He scratched his head and sent us to hand out WB bags, which we did for the next 3 hours. After we were done I went back to his desk and asked if I needed to check out or anything to get credit and he said he wrote my name on a piece of paper and would put it in the computer later that night when he got to the on-site volunteer check-in. He said, "You will just have to trust me." I don't know if I ever got credit or not. I didn't need a badge so I never went onsite to check and get a badge for doing that shift. I hope I did though and they don't think I was a deadbeat, so I get invited back to volunteer in 2015.