Crowd noise is always a problem. I agree with anodyne33. You have a very nice setup, but because you are taping acoustic sets it is much harder to drown out the crowd. Getting higher (the mics that is) should help, and the more direct - line you can get the mics toward the stacks, the greater your chance of drowing out crowd noise.
If you can get closer all the better still. The more crowd noise behind you the less for your mics to pick up.
If you find anything you try that is helpful, please come back and post what you did. Since you tape a lot at one venue, maybe something unconventional is worth trying with your mic placements. Walk around and pay attention to the sound and how it changes. You usually will find some sweet spots.