If Apple Pay lives up to what everyone expects than people may favor stores that use this secure and convenient method of payment. No store can afford to lose business because of using a payment method which is not secure . Look what happened to Targets business after their payment system was hacked, they lost millions of dollars of sales and profits.
Watch how fast stores adapt after the launch.
As merchants not supporting Apple Pay see a loss of sales they will adapt to Apple Pay.
People shop where the conditions are right meaning Price, Selection, Courtesy , Check Out experience and Payment method excepted.
While it's a bigger battery most likely it will provide little if any additional battery life The IPhone 6 is expected to have health monitoring functions that will constantly be on and use more battery power
In any case the Iphone6 will be great