Especially the consulting companies are doing this. And, all these ghost job requirement from green card and h1b should be removed. There must be no incentive to post ghost job.

Yeah, on the H1B there seems to be a separate issue. Posting a job listing that is intentionally hidden or otherwise not going to get bites. That way a company can say that they couldn't find a candidate and have to hire someone in need of a visa. From what I understand they do this to undermine wages as well as having a ̶e̶m̶p̶l̶o̶y̶e̶e hostage who won't complain about poor conditions because they don't want to lose their visa.