> Touch-up paint will make the scrape less noticeable, but may not last.

I used Honda touch up paint on a deep scrape on my bumper (exposing
the black part of the bumper) about 4 years ago, and the touch up
paint has not worn off or chipped. Of course it won't look quite as
nice as a body shop job, since the touch up paint won't be perfectly
smooth, but seriously it's not worth going to the body shop for that.
You'll get bumper scrapes again in the future, will you take it to the
body shop every time?