There is one exception to this. If you do both lith printing and use standard developers, you can actually contaminate your lith developer by using the same tongs as for regular chemistry. Lith printing used to drive me nuts until I started to thoroughly scrub my developer tray after using regular chemistry.
Thanks for the tip! I will likely try lith at some point (especially after seeing all the great examples in the gallery). Trays seem to have bred in my darkroom, so it shouldn't be a problem (I KNOW I didn't buy more than 3 8x10 trays, yet there are now 8).