I think this is actually a really smart idea from a business perspective - Hybe is looking to continue to diversify their mix of groups and this lets them fast track new groups with a built-in fanbase to start with. Particularly for idols, let one of the other companies spend the money and do the work on the training, while you can maximize your profits by launching those idols. Plus they have the potential to spin a PR story - someone who was released from Big Company X or Project Group Y and thought their dreams were over but now has a second chance etc etc. 
I'd also point out though that Hybe is not alone in doing this. (I feel like they are certainly more transparent around idols from other companies, but the other companies in the Big 4 have also scouted moderately well-known people. I think it's a bit of exaggeration on some of these to say they're "famous.")
