While I certainly don't enjoy it, I feel it gets necessary after a while. I don't mind packing a ton of clothes to last all week nor do I mind taking it all home dirty.
My problem, and maybe it's just me, is that we bring a little pop up hamper and keep it in the closet. It fills up every few days and I guess I could pull the luggage out from under the bed to empty the hamper. It's not really much harder to toss it in the washer.
I agree with the pp's who said bathing suits really smell after being in the ocean. I could probably have us all wear something more than once but my boys tend to stain their clothes often so they usually only get 1 day at most from anything. For dh and I, I just like that clean clothes feel and smell.
I didn't find it difficult to do laundry at all. The machines have a timer so I know exactly when I'm due back.
I found the atmosphere generally polite but then again I do laundry early, like Mon or Tues and by Fri I can pack all dirty stuff to take home. During one wash load, I ran into a guest that we had previously cruised with. The time slipped away and I was a bit late returning. To my surprise, some kind person spent the $ and put my wet clothes into a dryer. I put a post it on her washer to thank her. To pay if forward, I had only a few mins left on my dryer load and someone else was waiting for a dryer. I offered to put her clothes in my dryer once mine was done. She was thrilled; left me some quarters and ran off.
It's a shame people sometimes have to be so mean/selfish about the whole thing.

I would never do laundry near the end of the cruise just for this reason.