Angels We Have Heard On High?

My office manager and I were looking for the perfect piece of advent art for the cover of our Christmas Cantata bulletin.  We decided singing angels wold be appropriate.  The first Google image search made us die laughing!

Middle Guy: I'm here for the band...who are...wait, what are you guys doing?!

OK, seriously!  They look like the Bee Gees.  The one on the left appears to be playing a pair of underwear.  The next one is holding...a rainstick?  Then we've got the mandolin player, which is actually a legitimate musical instrument.  I'm not so sure about the two on the right, but the one holding a long black thing looks like he's smoking something out of it.  No one holds an instrument like that.

Maybe the artist got confused and thought the title of the song is "We Have Heard High Angels."  That's the only logical explanation for whatever is happening in this picture.