Thank,
Hellbilly
What I said still goes. You have to ask yourself what possible outcomes there will be if you actually have to use your firearm and under varying situations.
Also, I look at the track record for trouble at the venue. If it's record is one of few problems, even in the parking lots, then I'm more comfortable carrying only pepper spray. If not, then I probably won't go.... but if I do, it'll be armed with lethal and non-lethal options.
So there are a "few thousand" people there to watch the music and some thuggish guy decides to take out his frustrations on you (or two or three guys). In a crowd like that, if your assailant(s) resorts to physical contact and you unlimber that hogleg, some 3rd/4th party might see it and try to stop you (thinking you're the aggressor).
Or ... simple push suddenly becomes several punches that knock you down. Can you hit your assailant with blood in your eyes and between all the stars you're seeing?
If you can...and do... then what? Two thousand screaming fans turn into a panicked mob seeking cover or a way out. And you're on the ground. Or nearby security didn't see the fight, but swarm all over you because you have the firearm.
Even in the "best case" where your assailant brings his knife to your gunfight, you sustain a cut or stab wound and defend yourself, you may be jumped by well-intentioned audience members who don't know what's going on.
One reason I quit going to certain concerts that sell alcohol is that some people get reallllly stupid when they drink too much. However, the best fight I ever saw was a 6'1" jerk starting in on a 5'9" guy... and getting his clock cleaned by the guy's 5'5" girlfriend! She was a martial arts champion. Took the big guy down with about three hits, grabbed his wrist and made him squeal like a girl.