Daveyboy must be yanking our chain :W here is my idea of a Garbage disposal for the sink in an RV. http://www.chefscatalog.com/product/20370-sink-strainer.aspx?sourcecode=DW4GGP436&device=c&matchtype=&network=g&gclid=CNzD6_iivLcCFWcV7Aod0nEAMg Pull the large stuff out by hand, rinse the small particles into the screen and take the screen and dump out the collected stuff INTO THE GARBAGE CAN! Small food particles etc washed down the sink drain can make your grey tank smell worse than the black tank. However, Your rig, your choice.
Good Luck, Great camping!
BBuchorn.