Subaru Repair: Forrester wheel bearings, wheel bearings, synthetic grease

Question
I have a 2000 Forrester. Only 67K miles.  Here is the schedule of wheel bearing replacements that it has received:

Oct 2001 - right rear
Apr 2002 - both rear
Nov 2003 - both rear
Apr 2007 - left rear

What's going on?? I suspect 2 possible things: Subaru bearings are inherently bad (in which case, wheel bearing problems would be common with this model); or, something else is wrong with this car - something that causes the bearings to wear out abnormally fast.  Local dealer unhelpful - shrugs it off as a "dunno".  Any suggestions on how to prevent more wheel bearing problems in the future?
Thanks, Kurt

Answer
Yes the forester does seem to go through wheel bearings.At our shop we have found that ,cleaning the knuckle in a parts washer,using high quality synthetic grease and paying close attention to wear on the hub,has yielded a better repair for our customers.Other than that, the alignment,tire pressure,AND the wheel torque,Can contribute to the problem.

Justin
All Wheel Drive Auto