I hope the contributor of this comment will not object to my giving his comment the status of a post as it makes the point so clearly and concisely:
The placebo effect can be very powerful, especially if the one receiving the placebo is very gullible and susceptible to suggestion.
That is why pinhole glasses work for some people. They really believe the hype. This is why some people see the image of Jesus Christ in a fried egg or in tree bark.
This is why it is comparatively easy to bilk an elderly peson out of their life savings.
Pinhole glasses may not be illegal, but selling them flushes one's self respect down the toilet.