We did 107 days in our 5'er this past spring, summer and fall and there are 4 of us. DH, myself and 2 DDs, aged 9 and 6. They definitely produce dirt when they are camping. We were camphosting in MD and we asked the other camphosts about laundry. There is 1 set of W/Ds for 8 camphost families. We tried that, but trying to adjust around others to get all of our clothes done was a real pain, so we went to the local laundromat. We had 4 washers going and then 4 dryers. We washed clothing for each of us, then a load of whites, sheets and towels. All 4 of us participated, not just Momma. It took us less than 4 hours, we had books to read while we waited, we worked on a couple of crafts and we talked about what we wanted to do after the laundry.
Granted, it was not the most pleasant time we have ever spent, but the girls did learn how to sort clothing, fold their clothes as well as towels (they are expert towel folders now) and even sheets. It was good to have the DH with me, but to be honest, he went to the laundry with a small amount of clothes right after we got there. He's a good'n.