You don't wanna see the place one of the places I work at - 4 heavy JBL speakers, all hung by eye-bolts and chains (I can only assume the eyebolts are screws - I can't imagine anyone taking apart the speakers to put true thru-bolts in...), 4 chains per speaker, all hung off of 1.5" pipe sitting on rafters. We use a similar system to suspend the pipes for lighting and drops onstage.
I'll be pushing to upgrade those speakers this coming off-season, with actual flying hardware, even if we're still using the pipe to hang it from.