what would i actually do if i were at a show and the band started praying?
i wouldn't react immediately. i mean, i'd have to get over the shock of it, first. it would be a weird thing to experience, and i'd have to actually process it, first.
but, you can be pretty sure that i'd either get up and leave or at least go out for a smoke, until the set is done. it would clear me out of the room, without question, and there's not much chance i'd come back to finish the set.
i don't have any clear memories of this ever happening, mostly because this is probably something i'd catch well ahead of time, but i have walked out on bands and djs (the latter more often) for being openly misogynist.
again: i'm not interested in banning things. i'm a free speech advocate, up to the point of calling for actual violence (unless you're talking about killing nazis or other nazi-like extremists, such as islamic fundamentalists, in which case calling for violence is a necessary form of self-defense, and i'd not only not ban it but advocate it). but, i have a strong ideological opposition to any kind of public prayer at all, and i couldn't remotely support somebody doing it in front of me - i would vote with my feet and clear right out.
i don't know what the show was like tonight, but i hope it was secular and i hope people had fun.