This would never work. "Medium-high switching barriers" is a fantasy. The barriers are insurmountable, and not just because big retailers like to use in-house technology.
Every retail store is carefully engineered to make you walk around more. They want you to walk past things you didn't intend to buy and then buy them.
Ever wonder why household necessities are always at opposite back corners of grocery stores? They want you to spend as much time there as possible and pass as many shelves as possible.
Yes, there is a "problem" here for consumers, but it's one they will generally solve by using Amazon or the online pick-up systems that stores already have. You can already browse the inventory of stores and have your items waiting for you when you arrive.
Furthermore, because every store creates this problem, no store has an incentive to fix it.
If Target, for example, were to spend money on "TailSearch" (a LOT of money) and minorly improve the user experience at the cost of much of their sales volume, they would be screwed.
And what would the real benefit for the user be? Do you go to stores because it's easy to find things or because they have what you want at the price you want?
This is simple technology, and it could easily piggyback on the databases that tech-savvy companies like Wal-Mart already have. There's a reason they haven't done anything like this yet.
