The only music I've ever had in the churches I've ever been to (CoS mostly which is Presbyterian; some CofE as well which is Anglican) and they either had a piano or an organ: the CofE one had a choir as well. The idea of a full band at a church service just seems really odd: I mean why do you need it? That could be a bit of the Scottish sentiment shining though though; I don't know...
Uh, do you expect songs like
this to be played on piano or organ? That song is of course by a guy who played in influential post-hardcore band Thrice, who recently did a reunion tour with La Dispute, one of my favorite contemporary bands. You think he's going to compose piano and organ music? Or for that matter,
this?
Besides it's a church where people have times gone dancing in the aisles and even crowdsurfing. How do you do that without a full band?