yup it sucks, especially when you have spent a lot of time, or money on new paint or bumpers.
Like with mine, the very same day that I put them on I drove home, coming the other way on the 595 was a gritter, I got a feeling about it, pulled right over into the verge and stopped, few cars went past me, then it hit, BANG BANG SMASh, took three massive chips ou of windscreen and several HUNDRED chips out of bonnet, BOTH FRONT wings, my new bumpers

the ROOF, and BOTH A pillars.
I got very very pissed off and complained to the council wherupon I got a normal 'wear and tear; type letter written back. now have to put up with holes in windscreen and a few rust holes on bonnet (as I couldn't find my ouch up paint_)