Photographing the price labels and then comparing each one during checkout for a big trolly of groceries? Spending an extra hour to make sure you weren’t overcharged $3? Assuming your time has a nonzero value (I’m not sure of that actually), it sounds like this is costly for YOU
No, I'm not spending an hour on verification; what are you, a government contractor or something?
I've already got my phone out, because that's where I stick my shopping list sticky note. I already watch prices and frequently catch mistakes at the till. But I trust that the paper price tag won't change, so I just tell the cashier their system overcharged me and they fix it. Occasionally I'm hit with an unexpectedly large bill and spend an extra 30 seconds or so to figure out what's going on (the answer is usually cheese).
But if they change to electronic price tags, you bet your ass I'm gonna spend that extra few seconds per item so I have evidence on hand.
Plenty of people do this already by memory, if they're the ones that do the shopping regularly and are familiar with pricing. Several times I've told the cashier that an item was on sale or a different price than advertised and not reflected on the ticket. It didn't take an hour, it took less than 5 minutes.
