More than likely if there's not enough customers using Apple Pay, then the company is not going to make it a priority for training their employees on what it is. I only tried using Apple Pay two times in the last year at the drive-thru, and I found the experience counter productive for me and the cashier. First off, the cashier had to stick the AP reader out of the window so my phone could be scanned, and because I was paying with debit card, I still had to punch in my pin number. It would be far easier to just hand him the card and get on to the next window.
I don't know if AP is ever going to be as universal enough to have to carry my cards in my iPhone case. Like I said, AP works great at SaveMart, but in other places I find it hit and miss. I would really want my phone and watch to be the only thing I need to carry with me to pay for stuff, but that's just not going to the be the case. Apple is a multibillion dollar company, but that doesn't mean they rule the world.