Interesting Experience this Memorial Day weekend

The weather in Wisconsin has been horrible - cold and rainy most of the Spring, even snow some days. So I was looking forward to when it warmed up and I was able to go visit a local nudist "farm". It a small location - they have a pond out back where people come to lay out nude and meet with friends. I've been going here for the past four years. Not frequently, but maybe 3-4 times for short periods of time (no more than an hour). During these visits I've met and talked to the two owners and a few other people. I was finally able to go on Friday. Everything was going good on Friday until one of the owners came down and said she didn't recognize my car, and had I filled out their liability waiver form and paid. I hadn't paid yet, but intended to on my way out. That was my mistake and I'll admit to that - I even told her that and paid right then and there. She claimed they had never seen me before or my car, even tho I'd talked to them before. Thought nothing of it. Got an email later that night. They did a background check on me, and because I have a theft conviction back in 2012, and they had no record of me ever visiting them before, I was not welcome on their property. WTF!? When did having a clean record become a requirement for laying out naked by a pond? I understand it is their property and their right to not allow me on their property. But their reasoning is nothing I've experienced anywhere else. Just makes me sad.