Depends. If a rig is already dented, and not worth fixing, then have at it, thrash away.
My truck had many dents when I bought it back in 2004. Both front fenders have dents...
Rear tail gate dented in, cracked, rusting and barely working...
Kind'a rusty frame...
Bed has a ton of drilled holes from a previous owner...
...and I kept all the original dents and the stale, faded paint.
...and had I junked it, I wouldn't be doing this today: