It is true with a lot of stands, especially the cheap ones with rubber tube over metal frames. Hercules stands are generally safe for nitro finishes though, that is what I use with mine and I haven't had a problem. If you are going to invest $1000 in a bass you might as well invest another $50 in a stand to protect it.
I use this one:
http://www.musiciansfriend.com/accessories/hercules-stands-single-guitar-stand-with-folding-yoke
So true. I owned a music store years ago when every finish was nitro and the only stands and hangers were rubber padded. Had to discount quite a bit due to "hanger" damage of the finish. Finally started having terry cloth covers made for the rubber parts and that stopped the damage.

