Question

What term would an economist use to describe what happens when a shopper gets a “good deal” on a product?

Answer 1

The term would an economist use to describe when a shopper gets a "Good deal" is "Black Friday"

Now the reason behind black friday is it is a day full of special deals and heavy discounts, it's considered the kickoff of the holiday shopping season

On Black Friday, it's common for retailers to offer special promotions and to open their doors during the pre-dawn hours to attract customers. The promotions usually continue through Sunday, and traditionally, brick-and-mortar stores see a spike in sales.

so now it is commonly used term for a Good deal in economics