Interviews are so easy to scam

(Copying this from a recent blind post)

Just talked to another engineer. She told me this:

Suppose that I am a meta engineer. I am to take your interview (you are the candidate).

I'll get in touch with you before the interview(using any app/website). I'll tell you that you should purchase my course titled="Tips for cracking meta interviews by meta engineer" as it will greatly enhance your chances of success. You, in the heat of the moment/nervousness, would probably purchase the course. In the course session, I'll inform you about all the questions that I intend to ask you in the actual interview along with the answers that you are supposed to give. I'll inform you to keep everything a secret.

I can also ask another meta engineer to do all the same stuff as above(the other engineer will disclose all the questions that I intend to ask you in the actual interview) and in return, the other meta engineer will give me 50% cut of what she earned by selling her course.

This is definitely difficult to pull off in case of multiple interviewers for a single interview round but not impossible.

And interviewers have started charging money for referring candidates. They don't ask for money directly. They simply say="Purchase my resume review course". They take money from everyone but only refer those candidates whom they think would be highly likely to crack the interview depending upon their resumes. This increases the chances of the referrer getting the referral bonus later. Also, this scam can be combined with the above scam if the interviewers and referrers are willing to join hands.

I bet these things must be happening in non-SWE/other professions also. If companies don't financially incentivize interviewers separately for participating in an interview, such situations can't be minimized.