Mine "played dumb" about the 2 boxes full of cut up squares on the back of the toilet for 2 weeks before asking. I told him what they were for, and he said it was just gross, and he can't believe I'm "washing poo w/ our clothes". I told him if he knew about all the ammonia from his sweat, hair from his body, skin cells, chemicals, and everything else that gets into our bodies and clothes, he'd run around naked for life. I wash them w/ our whites on a 2 hour "sanitize" cycle, and he doesn't get that organic waste breaks down easily. He doesn't realize how much paper crappy yucky paper smears waste, and cloth just does not. He just doesn't get it, but he doesn't get a lot of things. My son won't do it either, but DD and I are cloth girls, and we talk about how the paper in public sucks, and laundry day (sanitized laundry anyway) sometimes has us using paper in a pinch for a couple of hours if we run out of cloth. I LOVE CLOTH!
As for paper towels, I can't win the battle. He runs to Costco if we get low on a few rolls. At least we're cutting somewhere, even if it's girls against boys!