What DID happen last year with on-site camping?

Does anyone know why on-site camping set up on Thurs was a bit of a mess last year? We got there early Thurs am to get in line and were #80 – so should have gotten an ok spot. When we got into the camp ground Thurs pm, however, almost all the camping spots to the right of the entrance where we needed to go with our pop-up were covered with tarps to “reserve” the spaces – no people – no vehicles, just tarps covering the ground. We weren’t sure how this had happened as it hasn’t occurred previous years – and we’re hoping it won’t happen again this year… Any insights?

Did you ever figure out what happened?

I watched one person jump out of a vehicle with numerous tarps, run in and line the creek with multiple tarps. All prime spots. Folks are getting innovative.