Permabanned
The whole thing wouldnt be such an issue if they had some respect for where they ruck up - if they didnt leave places looking like a rubbish tip costing us thousands to clear up after them they might get a bit a slack moving about
Nail on head, it's their total lack of respect for others that prevents us respecting their choice of lifestyle.
If they did clear up after a stay, they might impress the landowner to allow subsequent travellers.