If it's like most front wheel drive cars like my Jetta, which I've had the
pleasure to work on a few times.

( In order to get to the brakes, you
have to remove the cotter pin and nut to release the rear drum. Along with
the drum comes the bearings, which should then be protected from dirt,
cleaned and repacked. When replacing the rear drum, a new inner seal has to
be used (did they charge you for one?) with the inner bearing behind it and
then the outer bearing is fitted. Next the washer and nut have to be
replaced and TORQUED into place. Usually you tighten it until it becomes
slightly hard to turn drum and then back off on it until you can move the
washer with some slight resistance. It's a 'feel' kind of thing. If they
just tightened the hell out of it, that's what happened.