If you just got a call, why did you even admit that you have been anywhere near the store?

You may say that they found you because of your license plate and presumably, you would be recognized (by the clerk, because of cameras, etc.). Fair enough. But until and unless the police arrest you, or you get any official papers, you can just ignore any calls from the police. If they do arrest you or send you something, let a lawyer deal with that or be present. Don't make it easy for the police. Police resources are limited, and since you were not arrested at the time of the incident and the police did not come and get you, make it more, not less, hard and expensive for them to deal with a matter that is certainly not their main priority.

You may want not to drive that car. Traffic stops are a cheap way to find people without looking for them too hard.