Also note that this might not be a one way street. They might use brain machine interfaces to stimulate your brain according to the ads you are watching. E.g. you watch ads for beer and you get the feeling of beer taste on your mouth or you watch ads for bread and you get the smell of freshly baked bread, etc. Or when you are in a store, the implant will give you a serotonin kick when you foveate on a specific product (whose manufacturer paid for that kick). etc.

It's creepy af. But 20 years ago when you told someone about the privacy intrusions of smartphones, people would've been creeped out as well so I'm pessimist and saying it will come.