Hi James W
Don't see why you can't go to the north end of the beach, textile or not, and cover yourselves in the greeny/grey mud to your hearts content.
When Julia and I visited in June, some wore trunks/costumes and some did not. Never saw anyone chucked off (although perhaps there was a hard stare if your were not bare. (Is that poetry?)).
Why not just do what you want? Its a free world and there are no rules to say you can't cover yourselves in mud if you want to and keep your cossies on!
Best wishes
PJ