Anytime you are not using cash, it reduces the pain of paying. That's not just logical conjecture, but science.
Research has found that consumers tend to spend more money with a credit card than with cash or a debit card, and the expectation is that new mobile payment tools like Apple Pay will have a similar effect.
In a study at MIT, MBA students were offered a chance to bid on tickets to a sold-out Boston Celtics game. Those who could pay with a credit card were willing to pay twice as much as those who would have had to go to the ATM and pay with cash. Another study, aptly named "Monopoly Money" and published by the American Psychological Association, also found that consumers were more conservative when they had to use cash instead of a credit card to pay for a restaurant meal.