This issue has always seemed unusual. Many ,many campgrounds state "No grey water on ground." Yet then there is no way to dispose of it other than hauling to a dump station. Tent campers are not equipped for this.
Just what do the owners expect those without waste tanks to do? Drink it?
If they were truly concerned they would provide moderately easy disposal. A Georgia State Park we stayed in had grey water only dumps near the road about every 5 sites. That is reasonable,but that was the only time I have seen it.