I happen to agree with you, but it's also worth mentioning that solving whatever problem is creating the need to post ghost jobs in the first place would also make posting them unnecessary (presumably insecurity about the company's ability to assess, hire and retain high quality talent.)
But those are very hard, company-specific problems to solve, hence my agreement :-)
Not really. Make posting fake jobs illegal. Strengthen some whistleblowing laws. Watch as it stops.
Sometimes it's sending false market signals: a company that's hiring must be doing well, right?