I previously worked in the payment processing industry with many years focused on grocery. I can say without a doubt that grocery stores will not do anything that will slow down their checkout lanes. That means that bitcoin payments must be integrated into their POS
(read my blog about it) and be almost transparent to the cashier. Target is in theory a good target (
) for calls of Bitcoin support but I think they are be too big of a company to sway. Either they will decide to do it, or they will decide not to. Maybe the burn of the recent hack is enough.
There are TONS of small to medium independent chains of grocery stores all around the country. Those are more likely to try something new, but again, only if it's integrated into the POS they use today. These small to medium companies use NCR, Retalix, fujitsu, and a number of other POS systems. Support could be added to these without introducing new hardware by printing a unique QR code on the receipt and development to make the system aware of when the transaction hits the block chain.
The thing is, grocery stores are the most vocal about payments issues. They're sensitive to long authorization times or system outages because their customers are sensitive to them. I suspect it's because they spent all this time packing the cart with groceries and there is usually always a line of people at the check out lane. If the authorization isn't going through as fast as they expect, embarrassment and primal instincts begin to kick in and it's like backing a wild animal into a corner
And that is just the regular customers. When you start dealing with the EBT card holders, kick that reaction up a notch or three. Ok I'm exaggerating some but they will absolutely lose customers over outages.
Anyway, my point is that customers are used to getting authorizations in under 3 seconds and many of these store chains have dedicated network connections to their payments processor to ensure it. How many times have you sent a bitcoin transaction and had it take 10 seconds to show up on the network? Not a confirmation, just unconfirmed. That shit would not fly in the grocery business. No matter how much they save, they will not start using a technology that is inconsistent in what would amount to "approval" times. The reason is that payments issues piss the customers off so much that they will walk out, leave the groceries in the cart, and never come back.
There are nuances to the payments industry that many don't understand and this is one of them. Bitcoin just isn't ready for grocery.
In my opinion the most likely adoption path will be...
Ecommerce
micro-merchants (square)
Food and Beverage
Brick and Mortar Retail
Petroleum
Grocery