Sales Magic is an ability that all of the great salesmen throughout history have had, and nobody has Sales Magic in more abundance than J. R. "Bob" Dobbs as he is/was the greatest salesman who ever lived. Sales Magic allows someone to surf the Luck Plane and use the mind control aspect of Time Control to persuade people to buy things. Only a true SubGenius of Yeti ancestry is capable of using Sales Magic.
The Conspiracy also has ways of getting people to buy things, but someone who is persuaded to buy something they don't need by the Conspiracy always ends up miserable due to the False Slack it provides. Someone persuaded to buy something they don't need by a SubGenius using Sales Magic is always 100% satisfied.
Here is a video showing Rev. Ivan Stang using Sales Magic:
This urgent message from J. R. "Bob" Dobbs tells of how "Bob's" grin has been stolen, and he has lost his Sales Magic abilities: