I'm going to start by saying that I pretty much agree with you that it's immoral to knowingly screw people over. Now with that out of the way, I think there's

I'm going to start by saying that I pretty much agree with you that it's immoral to knowingly screw people over. Now with that out of the way, I think there's more of a gray area here than you might think. While there are many situations where people enter into a transaction with the belief that it's a win-win for everybody involved, I think there are legitimate situations where you can trade with people ethically while also believing that the other person is making a huge mistake. Bitcoin is a pretty great example of this. Suppose I'd been gifted a bitcoin in December of 2017. That was right around the peak of a huge rally for Bitcoin. If I'd sold it to someone for $15k I would have thought that the person buying it from me was an idiot. They may have thought the same of me. As long as we were honest with one another, that seems okay to me. The situation with Hertz was just kind of weird. It's as though I was taking out the trash one day and someone walked up to me and offered me $1000 for my trash. I don't really have any strong moral intuitions about whether taking their money is okay because it's such a goofy and unexpected thing to do.