"On another tack, I find it interesting that most bands who responded seem to charge more for weddings"

Charging for music is often finding a mid-point between "what are we worth" and "what can we get"! Generally speaking, wedding budgets tend to be higher than, say, birthday parties, and musicians can get more because people are prepared to pay those prices for those sorts of functions.

A case in point is Near Year's Eve. I don't do them any more but, when I did, such was the demand that you could virtually - within reason - name your price, or at least find a venue that was prepared to pay your price. It used to be a standing joke, in my musical social group that if you couldn't get a gig on New Year's Eve, you'd never get one.