Since I was a young guy (19 years old), they wanted to know if I was going to invest enough time into their company. My answer was: "Right now, my top priority is to gain a lot of work experience, and pursuing academics is not on my radar at the moment." I think they liked it, but you could also tell them: "Although school is not on the top of your mind, you would like to pursue academic goals some day in the future in order to develop your career." This will give the interviewers an opportunity to sell Walmart's excellent opportunities for career advancement and training available to their employees. If they try to convince you of how good Walmart is, then you know you made a good impression.