I think this topic has probably been flogged to death by now.
Keep things in perspective, and try not to take any of this stuff personally. This is not life and death, it is just racing, an evenings entertainment.
The problems start when guys like yourselves with all good intentions try 'rectify' the matter, maybe do a little unwanted education. If you really feel serious about this matter, print up some flyers on MX etiquette, make it humorous, witty, and insightful, and hand them out at the arena, who knows, you never know. you may get through to those who need a little enlightening. Try to refrain from direct confrontation, that is unless you think you can approach the situation in a level headed manner.
The last thing I want to see are fist fights, riots and bottle throwing in the arena.
Think of it as light hearted ribbing, if it is anything more serious than this, then we have a problem. I would hate to see the finger been shown in the crowd, spitting or other disrespectful outrageous behavior.
If someone boos, let it go, cheer your guy on even more. A good lusty boo, or a heartfelt cheer does wonders for the spirit (must be something to do with the 2 stroke fumes !)
Most importantly, have fun.
If you can turn to the raucous guy next to you at the end of the evening, and with a big smile shake his hand, and say "Man, this was a fantastic evening", and he grins and shakes your hand, then it will all be worthwhile ! :)
I can just see my fellow DRN'rs sitting far away from me, with this 'I don't know this guy look on their faces" :) see ya all at Dallas SX 2002.