Rear suspension

I drive a 2001 Camry LE I4. When I go over a reasonably sized bump, my rear suspension makes a louder thunping noise than the front. The front sounds fine, but the rear was bothing me. It wasnt anything lose in the trunk either. So i took it to the shop to see what the problem was. The guy said it was for sure bushings that were no longer tight, but that it was nothing at all to worry about. Besides, to fix it, he would need to take the entire rear end off to access the parts. Basically it wasnt worth the cost/man hours it would take to fix an insignificant problem. Has this sort of thing happened to anyone else? Im not nervous or anything...just purely curious.