Without a doubt, launching Apple Pay was a major undertaking for Apple, the credit card companies and banks. What we're now seeing is that there are many more moving parts and players in making it a mainstream payment option. There needs to be buy-in from major chains as well as small business.
Credit card processors, be they mobile processors like Square or more established retail-focused companies, need to position Apple Pay to merchants as a next-generation payment option that in itself has the potential to attract and retain customers. After all, if you're excited to be able to use Apple Pay, you're likely to keep patronizing merchants that accept it.
There also needs to be a push for greater awareness of where Apple Pay is accepted. That can come from a variety of sources, including Apple, merchants themselves, and even outside parties.
There also needs to be a push for awareness on the part of Apple Pay users. Asking small businesses whether they accept Apple Pay will encourage its awareness and potentially encourage adoption. You may even find out that stores not advertising it actually do accept it.
Not all of these moving parts are working in harmony right now, which is the big reason that Apple Pay's growth hasn't been as explosive as might have been expected. There does, however, seem to be a coming together of the key pieces of the puzzle, particularly since the liability shift at the beginning of October. All in all, the outlook is positive. But it will take some time before Apple Pay is readily accepted every place you need to pay for something.