Well the companies and developers don't decide for every single material. In example what I expect is, that they program the scraper with rules to respect licenses of individual projects (such as on Github probably). And I assume those scraper tools are AI tools themselves, programmed with AI tool assist on top of it. There are multiple AI layers!
At this point, I don't think that any developer knows exactly what the AI tools are fed with, if they use automatically scraped public sources from the internet.