Ran into something new to me at the end of this years' summer travels. Reservations on weekdays after Labor Day are usually not needed up north so I did not bother to call ahead for my planned stop at a Wisconsin KOA. This had been our first (reserved) stop 2 months earlier at the start of our trip. At check-in I noticed that the charge was $2 more than before. I was informed that if we had called the day before and reserved the site it would have been $2 cheaper. I had never encountered this before and contacted KOA who said this was a policy option that each park owner could decide on whether or not to use. When I complained to the owner before we left, her only defense was that hotels do it. I feel that this is either a hidden charge for "drive-in" customers or an uncdisclosed discount for those who make reservations. Either way, I consider it a sleazy business practice even if it is only $2. I have stayed here numerous times in the past before this owner took over last year. At the very least, I think KOA should notify its' cardholders of this practice and each parks' listing should advise customers of the $2 charge for "drive-in" customers. In season, there may be some logic in knowing how many customers you are going to have, but when the park is only a quarter full afer Labor Day I don't see how is makes a difference. Additionally, this is not a resort or destination park - it is mostly overnighters. Has anybody else come across this "hidden charge'?