> They already run a large web store and they could have done this anytime but it's clear they have not.
I mean, they have but whatever. The part you're not considering is the immediacy of buying at a physical location.
Browsing online has a different set of tools the merchant can use to FOMO you into buying it. If you see something online you can easily come back to it hours or days later and reconsider; if you're there in the store you're probably not very likely to come back tomorrow. If you're going to buy something at the store you're most likely going to buy it during that visit, which makes you more vulnerable to surge pricing.
> They'd be caught very quickly if they did this in a retail store.
And the consequences would be... what, exactly?
Personally I'm waiting for the other shoe to drop; sign up for WalMart Customer Plus for $19.99/mo and skip the surge pricing!
=Smidge=