Camping

I'm a relatively new member to the caravan club always been into the outdoors etc and one of my first caravan club sites I ever stayed at was in the Highlands of Scotland in a tent! My question is what deems a site suitable for tents and others not, I stay regularly at Rookesbury and it is truly beautiful there with lots of grass, but they don't take tents, is it council bylaws that say whether they can or not or is it something else. Just curious.