I agree with the majority, you really did hit on a bunch of ignorant so and so's rock chick. I usually sing unaccompanied but really like it when a guitar or melodeon join me , i think it improves my timing which can be suspect. I sing with a friend in a twp part harmony sometimes, and it can be frustrating when the crowd join in not only the chorus but also the verses, however, I also see that as part of what music is about, connecting through music to other people, so on these occassions i put up and shut up.