Suppose I bake 100 brownies and try to sell them one morning. I sell some and as I'm packing up my booth you take one and eat it. You argue, "I was never going to pay for a brownie, I didn't want it that badly, and anyway you can't sell them tomorrow because they will be stale."

There is something deeply wrong and immoral about this way of thinking. The idea that you alone get to value someone else's work output to be zero and then take that output and claim it has no value, and that the taking causes no harm.

It is theft. But you don't want to be called a thief. So you play semantic games.