This doesn't surprise me at all... Just like bots in games. Selling a service that benefits another. Its shady, but definitely believable.
Also, what if this is an actual viable way to "market" for an open source project?
https://www.bleepingcomputer.com/news/security/over-31-million-fake-stars-on-github-projects-used-to-boost-rankings
I am fortunate enough to not market my stuff:
If somebody finds and can make use of it. Great.
In the other case who cares? Didn't hurt or cost me anything to publish it.
Fake GitHub stares have other implications: Typosquatting is a real issue and fake stars make it more convincing that it is the genuine project.