I think it turned out like this because supply control used to come from the time/resource limitation of making physical goods. If you wanted your product to be rarer/higher priced, even on the second-hand market, you needed to produce less of that item. With the computing age, putting software on disks is cheap and sending software via the internet is effectively free, and reproducing that software for free to send to anyone who wants it is both free and easy (less so now with blu-ray DRM but it still happens).
Nothing wrong with treating licenses as tangible digital objects: ie you get to sell YOUR license, but can’t reproduce it.
That’s how it works with physical media, and the postal system is a relatively cheap form of distribution (try mailing a 4K BluRay across the country: it might even be cheaper than bandwidth costs).
