Our CG is seasonal and occasional. 700 seasonal sites and 400 occasional sites. I have seen many a holiday w/e come and go with large crowds.
This is the first I've seen here or anywhere I've camped where people pull out and leave their bagged garbage on the site. Rows of campsites left this way.
My guess is one site did it and the neighboring sites followed suit. They were all left at the roadside as if it were set out at home for "garbage day".
The CG had to go around in a pickup and collect all those bags, thrown out chairs, boxes, etc. etc. Hmmmmph! Guess they never heard the saying...Leave only your footprints.