Sorry I just don't get your drift. You're suggesting that CSC motorhomers should let non-CSC travellers use their toilets, etc. But then describe your own contribution as letting someone use your shower. Well showers don't feature in self-containment; it's about fresh water supply and waste water containment. Ultimately our individual endurance is determined by the capacity of our tanks. If we allow others to use them, we may be reducing our ability to meet the mandatory need of 3 days imposed by the standard.
So, your beneficent provision of showers for the muddy campers didn't address the SC issue (they could have jumped in the lake to clean up which would have been no colder than they bog they'd been in). And their apparent reluctance to use the public toilets already provided just demonstrates the nature of the problem that the country faces. If I understand your comment about the disinfectant spray correctly (and I'm not sure I do) again that's wrong. If they have to crap in the bush (as distinct from choosing to do so when adequate toilets are available) they need to bury it into the organic soil layer and certainly not disinfect their leavings, to avoid killing off the very microbes and bugs that will break them down.
7m Fuso wide body, 420W solar, 230 A/h batteries, 2kW Eberspacher, 255L 230V Samsung fridge, 400L topbox, 195L fresh, 200L grey, Suzuki Jimny toad with 4.7m OK Prowler fishing kayak, MTBs.