Yes, I find the bottom of my mouse is not as dirty from picking up dust from the table because the cloth of the mouse pad does a pretty good job at keeping the bottom of my mouse clean. Plus, my mouse pad has a small cushion/pillow for me to rest my hand on when I am not mousing, so it keeps me hand nicely supported.
This is one of the reasons I use a mouse pad since it seems to keep my mouse bottom cleaner, and less dust can cover up the red LED light. Plus, my wood table does not get scratched up from the constant mousing movements, and the oils from my hand when I rest my hand on the table.