'Tis the season of American capitalism. Online shoppers spent $9 billion on Black Friday and $11 billion on Cyber Monday this year.

What is the impact of all this spending? And while everyone loves a bargain, is it possible that some items are just too cheap?

Author Tanja Hester argues that while Americans buy a lot, we may be leaving something on the table: our power to leverage change based on how we use our money.

Hester is a former progressive political consultant who the New York Times describes as the “matriarch” of the women’s FIRE movement. (FIRE stands for financial independence/retire early, an investment strategy that's gained popularity in recent years.)

Hester's new book is Wallet Activism: How to Use Every Dollar You Spend, Earn, and Save as a Force for Change. She contends that where we shop, what we buy, and where we donate can influence the fate of our society and our planet.

"I believe that we can make real change, and it's within our individual power to do so," says Hester.