Are the picnic benches bolted or chained in place? Can they be shifted slightly to make room for our tent in a small site?

Group campsite wood tables are loose, cement tables remain in place. Plenty of space for tents.

There is a lot of space for tents around there

They have a cleared space for tents on your site

They aren't chained but it would be difficult to move. Though if you are willing to put in the effort than yes.