This is the back right corner of my bumper. Just noticed it today.
TRIM ATTACHED:
TRIM PULLED BACK:
This next image is where the screw holds the trim pieces on. I'm going to get washers that fit the screws, and put them inbetween the trim plastic and the white plastic that the screw goes into. Should give it a slight gap to prevent rubbing, as well as keep it stiff so as to prevent more abrasion anywhere else.
Once I get the washers, I'll post pics of them and how the gap looks.