mrv@kluge.net

The rear bumper applique is just a clear plastic with dimples on it
that spells out "Prius." It sits on top of the rear bumper, to prevent
cargo that you slide into/out of the rear hatch from scratching the top
of the rear bumper. It would not prevent scratches from other cars.

(Several people prefer getting the black knobby rubber rear bumper
protector that's for the Matrix, compared to the cheap-looking plastic
rear bumper applique.)

To prevent the scratches that you suggest:
1: don't get a rental car
2: drive and park carefully
3: look at installing the 3M paint protection film (such as by Xpel,
Clearbra, Ultrashield, etc.). It's more expensive, but it'll cover a
far greater area of the car
4: look at installing some door ding bars/side rubber molding