Big Changes Coming To Reserve America?

I've not had issues with booking with Reserve America, but I have often wondered why there is always so many open sites sometimes when Reserve America says there aren't sites available. I know there are cancellations but one time recently we were at a local state park that has two 30 site loops. I had booked way in advance but the morning of our checkin date, I checked Reserve America and it said all sites were booked. I know they hold some sites for a first come basis but when we arrived the campground was only about 65-70% full. I have seen this on multiple occasions.

Burch