Standing in line at Starbucks, customers are presented with an array of options beyond just flavors and foam: They can pay with cash, credit, debit, a Starbucks card or with their mobile phone in two different ways.

That list is expected to grow in the coming years, not only at Starbucks but also at retailers around the country, and an enormous hacking of customer data at Target that was revealed five months ago has only intensified the pace of change in the way Americans pay for goods.

Usually, the conversation about where to go from here is presented narrowly, either in terms of the security of new cards or perhaps the convenience of paying by phone. But behind the scenes, there are other issues in play, including the jealous guarding of customer data. And there is an enormous amount of money to be made, especially for businesses catering to the cash-free consumer.

“There is money at stake all around the room, whether it’s the banks and payment processors or the retailers,” said Suzanne Martindale, a staff lawyer at Consumers Union who specializes in payments. “It’s a battle between the two parties.”