Two night stay requirement

So .... I'm traveling 1250 miles one way to visit my daughter this summer.
Should I have to pay for 2 nights to only stay one along the way?

I have run into that one time (Jenny Jump State Park PA)

I paid 2 nights stayed one and no problem. Still cheaper than a KOA. WAY WAY WAY cheaper.

Being new, apparently you have not seen t from the other side. That side that would like to spend more that two nights, up to a week or more, but cannot find a campsite because of people that reserve for part of the weekend a year in advance. Meanwhile, the rest of the week, the campsite sits empty, and unpaid for. And as there are more and more RVs and campers out there, there are fewer and fewer available campsites. Many of us are campaigning for minumum three day weekend reservations. We are retired, and cannot plan where we will be a year for now. But wherever it is, it will probably have to be a Walmart for the weekend, while campsites close by are empty, and unpaid for, because of one night reservations.

Now that I have said what others think but won't say, let's
see how many will tear into me for saying it.

Usually the requirement is only for reservations, but not for stays as such, at least in my experience. If you arrive without a reservation and they have space, you can pay for and stay for a single night as a "walk-in" camper. (Some states have moved to a system where walk-ins, at least after office hours, have to call and make a reservation on the spot via a hotline phone or a cell phone. They still generally permit one to stay for a single night.)

If you can tell online how many sites are unreserved, or get a person on the phone to tell you that, you can usually form a pretty good idea of whether or not a reservation is really necessary to get a site. If half the reservable sites are not reserved a day or week ahead of time, then it's pretty unlikely there will be a sudden mad rush to grab them all within that time. On the other hand, if only one or two are left, you are probably pushing your luck without locking a site in.

The state parks are not alone with that policy. Many commercial campgrounds do the same thing. Why would they want someone to book Friday night only, when someone will want it for both nights, if not more? Allowing a Friday night only all but assures that the spot will be empty for the rest of the weekend or more.

I run into this quite often when booking a long trip and need just one night on a weekend. It can be frustrating, but I fully understand the policy.