So maybe the idea is impractical for Ben. A lot of those little shops dont even use a scanner at the til. so maybe it cant be done there. fair enough.
but in fairness, you are using an extreme example (with added sympathy for poor ben the shop keeper that has to stay up all night or his business will close and his family will starve... ;-) ) to hammer something that really would apply to major retailers who are not gonna be closed down because of it. infact in your opening paragraph you use the word whole, all, every which just shows you are using hard/extreme examples to back up your arguements. have you anything based on the mean? an average case example? that applies to most stores effected by the idea? thats why i think your examples/arguements are pedantic and i dismiss them easily. come up with something that applies to the mean case and you'll have my attention.
as the mod said and i made clear a few times, this is an idea at a formative stage. it is not perfect. but again, using extremes to invalidate it is easy, and easy to ignore.
so in an answer to your question, ben can rest easy for now. in the long term, increased competition due to the listing on accurate up to date prices online may force him out of business but thats the free market and thats acceptable, right?
Theres nothing wrong with a voluntary site for whoever wants to participate and thats all it ever should be.