Some years ago I pulled into a campground in Moab Utah with my popup as a guy on a bicycle who was tent camping. They charged him the same price as they charged motor homes and fifth wheels. I thought how they ripped the bicycle rider off at the time.
Rip off?
Maybe, maybe not...
If you develop a campground and spend x number of dollars to build it, and use the proceeds from renting spots to support it, why should one "spot" cost more or less than another, a few square feet more, or less isn't enough to justify a cost difference.
Should a business "lose" money just because someone has a "small" camper as opposed to a giant one?
If a campground offers "utilities" such as water, sewer, and electric, then certainly it would be unfair to charge a non utility site the same as a full hookup site.
In the end though, "fair" doesn't always go along with a business, in business to make a profit.
If all spots in a campground are roughly equal in cost to develop, and maintain, but one had a nice view, or a shade tree, or... the business may choose to maximize its profits by charging more for that "premium" spot. They may also choose to charge more based on the size of your camper. If all costs were equal with regard to their expenses and maintenance per spot, that would be unfair, or a "rip off" however, it is just business... no different than options on a new car, etc.
In the end, the customer determines what the business can charge. If the customer will "pay" the price, the business isn't going to reduce the price.
Rob
Waiting for "someday" will leave you on your deathbed wondering why you didn't just rearrange your priorities and enjoy the time you had, instead of waiting for a "better" time to come along...