you get better products. the store gets better sales. it's a win win all around.

this is already happening and it's already providing value.

How do you get better products?

What does a filmed image give you that isn't reflected by sales numbers?

The goal of tracking isn't to make and sell better products, the goal is to create an environment in which the product you already got gets sold more. So essientially people who track you want to manipulate you into buying shit you don't need at prices you wouldn't pay unless manipulated.

Tracking people who would buy your product anyways isn't all that interesting: you've already got them.