1 John 4 : 1 ....... Dear friends, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world.
What's the problem? Just having fun! Why are you so serious? They should just feel like military bands! Jesus said that. "People don't live only in bread..." (Mathew 4:4) Do they need to be as decent as they always say in the Bible? They should enjoy themselves when they play, right?