Good point about the loos. In fact now you point it out, I remember I've encountered that problem before – can't remember if it was a C&CC site, but it was just a field and owner, otherwise very friendly, said he couldn't let me camp there cos he'd risk losing his licence or certification or something.
Which leads to the question of whether the Backpackers Clue sites have facilities and if not, do they allow digging (and is there even a suitable place to dig)? Presumably they're set up for backpackers so would have at least a primitive toilet block.