One thing to keep in mind that may be relevant: copies of non-digital things are different than digital copies.

Digital (meant here as bit-for-bit) copies are effectively impossible with analog media. If I copy a book (the whole book, its layout, etc., and not just the linguistic content), it will ultimately look like a copy, and each successive copy from that copy will look worse. This is of course true with forms of tape media and a lot of others. But it isn’t true of digital media, where I could share a bit-for-bit copy of data that is absolutely identical to the original.

If it sounds like an infinite money glitch on the digital side, that’s because it is. The only catch is that people have to own equipment to interpret the bits. Realistically, any form of digital media is just a record of how to set the bits on their own hardware.

Crucially: if people could resell those perfect digital copies, then there would be no market for the company which created it originally. It all comes down to the fact that companies no longer have to worry about generational differences between copies, and as a result, they’re already using this “infinite money glitch” and just paying for distribution. That market goes away if people can resell digital copies, because they can also just make new copies on their own.