I mounted some on the last trailer for the exact same reason. I mounted mine forward of the rear bumper 12 inches. I figured there they would not cause increased contact, but should protect the camper and the driveway. They worked pretty well. I am thinking about doing the same with the present trailer, as the rear entry door step frame hangs below the rear bumper a bit. BIL has the same trailer and bent his steps to the point of being unusable.
Current TV:'14 F350 Lariat CrewCab, 4x4 Short Bed SRW Diesel w/ Pullrite 2700 (16K)
Current Fiver: '15 Puma 295BHSS Anniversary Edition
Past TV: '13 F150 HD Payload SCrew EB, '08 Tundra CrewMax 5.7L, '02 'Burb 5.3L, '97 Dakota 3.9L
Past Trailers: '09 Wildwood LE 27RB, '02 Palomino Yearling RL, '87 Jayco 1006dlx