I cannot help but agree with you.
As we discussed last night, I never shot anything faster than 400 ASA and I did shoot some concerts. We managed to get those shots on film so why can't you with (just about) any digital camera. I am sure that if I went and looked through my books about music and bands I would find some pretty horrendous grain because some photogs pushed their film or used whatever high ASA film existed then. So be it.
But, maybe, one needs to think about this type of photography the same as a sport shooter does. There is always a moment in the action when the action (almost) stops. That would be the time to shoot. There is also a time when you have more light and you need to be able to combine the two to get the shots.
Small clubs with very little light are always going to be a problem but they are also, usually, the easiest to deal with. Both the band and the club want to get their names in print if they can. So shoot with a flash. Concert light is always pretty harsh and a flash photo is rarely going to look out of place.
And if you shoot color, put a gel on your flash unit so it looks like it's part of the show.