Don't know about Europe, but in America the choir loft seems to be a denominational thing. Russian Orthodox churches have the choir loft above and behind the congregation (and they sing a cappella). I have noticed that - at least some - Catholic churches also have the choir loft above and behind, too. Presumably, also Greek Orthodox, but that's just a guess.

I also found this. Apparently it has a lot do do with the age of the building, so in Europe I guess we would expect to find many more churches with the rear-elevated choir loft.

Very cool that they had Adagio for Strings playing at the gym!