music pastor to everyone: just show up when i get a wild hair

as stated before, i play guitar for my church. the band is fairly large. we have at least 1 electric guitarist and 1 acoustic guitarist (sometimes 2 of each), 5 or 6 horn players, a keyboardist, a pianist, a bassist, and a drummer. if you add in the 'worship leaders', you get the music pastor + 4 people. that means on any given sunday, the "worship team" is made up of around 15-20 people (not including the sound guys).

i got a mass email from the music pastor, where he basically said [sic] "we are doing a night service in a few weeks, so i need all of you to show up at 3pm on Sunday to play."

what? am i the only one who thinks this is ludicrous? he has 15 volunteers who contribute their time and talent for 5-10 hours a week, and because he gets a wild hair, he wants to have a service where he expects everyone else to just show up.

no questions about "when can people play for a nightly service? when do people have plans this month? is anyone up to playing in an extra service?" no. he made plans, and he expects us to show up.

it's completely rude. am i right? i understand that in a group of 15 people, there are guaranteed to be conflicts, but he could at least be polite enough to ask.

i think i'm going to tell them that i don't want to play, unless we have some fun music (for once).