Voting with my dollars. Retailers who have success with ApplePay will make no secret about it, and those that aren't using it have to compare their YoY numbers to the published ones of those using ApplePay. Using my credit card as normal doesn't send that message. Not that my spending alone is enough to sway an industry, but if enough people vote with their dollars, the message gets sent.

I guess I was really asking why you, as a consumer, care if a retailer supports ApplePay? Is the checkout experience that much better in your eyes vs an ordinary credit card? Or do you like the added security? Or something else?

All of the above. I don't like carrying my wallet, but I always have my phone, so being able to use it in place of my wallet is something I want. I love the added security - I shopped at each of the major retailers to have a breach in the last year, and got a new debit card issued each time, which is a huge pain the ass. And, in general, it pushes the industry forward, which is good for everyone. If ApplePay gains traction, so will Google Wallet, and Windows Phone will have the road paved to offer NFC-payments.