We've run into this in Arizona and Michigan etc. Seems there is a n outfit that installs their equipment and the camp ground doesn't have to do anything.
We had to log in and give a credit card. We paid for a week one time and then a day or a few hours.You pay by the day or by the hour, in one case. They make a fortune. Only time we used in Arizona was to pay bills. If we were headed to casa Grande or Tucson area we went to a MCDonlds etc and even a Wal Mart parking lot. We now have MIfi but haven't traveled with it much to see what problems there might be.