I'm not sure what copyright laws one might run afoul of doing as you suggest. Certainly copying things like that concert which is being sold in stores would be a big no-no. And with the RIAA willing to sue little children and old people, I'm not sure it is worth the risk.
I hate to be a wet blanket.
You're not being a wet blanket. You are pointing out a mistake I made and I appreciate it.
In essence, I'm envisioning a front to back "guerilla" operation, including people with video cameras at events.