My teflon fry pan is not dirt/sand friendly, Gavia.  I'll stick with a sponge and some soap and I wash the same way db does - cleanest first.  I highly encourage campers to lick their plates clean first too!  I prefer not to leave dishes out as they could pick up stuff from say, that Canada Jay perched on the branch above them, eyeing your crumbs.  :o  Since pots heat up, killing the germs, the real risk is on the eating gear.  All you other old Army guys must recall having to hot dip your mess kit BEFORE eating.  I also don't like having loose stuff around camp...a bit OCD on that. 

p(OC)d