I'm under the impression don't really understand the culture or history of obtaining Linux. Yes, anybody can sell a disk with Linux on it. You can also download that same software for free. The data transfer rates back in the day meant that getting a physical disk was the quickest way to get 500Mb of packages etc. Plus not everybody wants to bootstrap from a tarball and chroot into a system to finish installing from files on their current OS. Flash drives and CD burners were not common yet. Physical media were a way to spread Linux, not make a quick buck off it. There was nothing shady about it.