I am not sure that your information for England and Wales is accurate, I have wild camped a lot and without a problem, the worst that will happen is somebody might tell you to leave in the middle of the night. You also don't specify if you mean with or without landowners permission, with it is most certainly legal in Britain.
If it's in the Touratech catalogue then you don't need it
"You've got to think for yourselves! You're all individuals!"-Brian of Nazareth