> ESLs are ecological: they can be updated and they last for years, it saves paper and ink! This is utter bullshit. Prices and products don't change that often

Prices didn't used to change that often, but now they can be changed several times a day (or even several times a minute) using automated systems. Cell phone tracking and cameras can allow a store to get information about you and your income and they can use that data to charge you higher prices for everything, or to strategically increase the prices of the items you buy most often while monitoring and tracking changes to your buying habits in order to take as much money from you as possible. That's the entire point. It's not about ecological savings, it's about economical gains.

> ESLs provide better price accuracy, what you see is what you'll pay

Facial recognition at the shelf and at the register can keep prices consistent for you as an individual even while those prices change wildly over short amounts of time. I doubt they'll let you modify the price displayed at the shelf and still give you that same price when you check out though. It'd be risky. If you were caught it might be treated like swapping bar codes or like terrorism depending on where you are.

> Some ESLs are NFC enabled. You can tap your phone to get more infos on a product

Making you sure you've got your cell phone lets them pull data off of it and fingerprint the device. The goal is to use that info to gather real time feedback about you from data brokers, like how much money you have.

By all means, mess with these systems for laughs, but it's going to take actual laws with teeth and oversight to keep them from being abused.