Bad experience Lancaster KOA

The ADA requires employers to make reasonable accommodation to qualified employees & applicants. On the other hand, places of public accommodation (e.g. hotels, restaurants, and presumably campgrounds) are required to not discriminate against the disabled & comply with the accessibility guidelines. That's a not insignificant difference.

I doubt a campground's failure to provide shuttle service or waive an apparently uniform guest fee is an ADA violation, although if I saw multiple reviews describing the management's hostile attitude toward its guests, I'd look to camp someplace else.