A man walks into a brain store to buy a new brain

He goes to the clerk and says

“Hello, I’d like to purchase a new brain”.

The clerk replies with “Sure, here are some of our brains we have on sale”

“Here’s the brain of a physicist, 5 dollars.”

“Here’s our second deal for today. The brain of an anti-vaxxer, 10,000 dollars”.

The man, completely confused, asks “Why is the brain of an anti-vaxxer more expensive than of a physicist?”

“Because it’s never been used” The clerk replies.