Amazon opened a grocery store with no Cashiers

Amazon just opened it's first cashier-less grocery store in Seattle, and all you need is an Amazon account to shop in it!

The store comes equipped with plenty of cameras and sensors that have the capability to scan what you have as you bag up your groceries and/or walk out of the store and will automatically charge everything to your account!

My thing is what was wrong with grocery shopping before why keep trying to improve stuff that wasn't broke! 

Its also another way to spend too much money because you just putting stuff in the bag and not seeing how much you spent! 

But what are your thoughts on it!