I think the "one set of clothes" type of people on this board are more likely to have frame bags and 3 inch (or wider) tires, that I would have noticed.

And even if they were on this board, they should have paid. It was a state park with a designated hiker biker site, so if they were hiding back in the trees instead of in the hiker biker site, they were obviously trying to avoid paying. Although this occurred in a different state than the state I was from, I used to work for a state agency that ran the state parks in my state so this is a sensitive topic for me.