"When you put the convenience together with the affordability, and then you match that with high-quality routine health care, that's why this is such an appealing concept that I think will grow very rapidly," said Web Golinkin, CEO of RediClinic.
But, Golinkin admitted, his clinics didn't make money last year and probably wouldn't this year.
"We'd expect a clinic would take 12-18 months to get the cash flow to break even," he said.
There are still a lot of questions about how these store-based clinics will fit into the big and troubled picture of American health care.
"This isn't the answer," said Mark Smith, who runs the California HealthCare Foundation, an influential think tank. "It is maybe an answer to one set of problems we have."
Smith says these consumer-driven, store-based clinics will end up tackling only the easiest health care problems -- ear infections, strep throat and the like. But even that could make a difference.
"If we can't agree to take care of the cheap, simple stuff cheaply and simply, there's no way we'll be able to afford to take care of the expensive, complicated stuff," Smith said.
Others, like Alan Garber, director of the Stanford University Center for Health Policy, may support the general idea of in-store clinics but worry about the way these clinics could affect the rest of the health care system.
"One of the fears that I am sure many doctors' offices have is that the doctors will be left with the complicated patients who may not bring in much revenue but take an extraordinary amount of time," Garber said.
Some doctors have already come out against the concept of retail-based health care. In particular, the American Academy of Pediatrics announced that it opposes the use of the retail-based clinics. The group worries about the "continuity of care," the gathering of information about a patient over multiple visits and across multiple health care providers.
"I'm concerned that some things are going to be missed," said Dr. Denice Cora-Bramble, a pediatrician and the executive director of Community Pediatric Health at the Children's National Medical Center in Washington, D.C. "It's understanding what are some of the other issues in the life of a child that impact that particular encounter."
And then there's the Wal-Mart factor.
Wal-Mart is a retail giant -- the world's biggest. Each week 130 million consumers shop there.
And neither Wal-Mart nor any of the other big chains in this business are setting up these clinics for charity's sake.
"Retailers are getting into this because I believe they benefit from anything that brings the customer into the store," Garber said. "It's probably viewed as a great revenue source."
ABC News asked Bill Simon, Wal-Mart's executive vice president in charge of these operations, about the profit motive at play with the in-store health clinics.
"It's an opportunity for us to do what we do best in a segment of the economy that needs a little dose of Sam Walton's business philosophy," Simon said. "How do we straight-line from the health care provider to the patient rather than provide all the twists and turns that occur in the health care system today."
There's one way big retailers will hold down costs, by strictly limiting what the clinics do. No MRIs with their high-maintenance costs are done in these clinics. There are also strict limits on the kinds of ailments nurse practitioners like Sandy Branson are allowed to treat.
But for all the potential limits and concerns, it's clear many patients -- or customers here at Wal-Mart and at other stores -- are ready for the revolution to begin.