It’s something most kids have done, taken something from a store after a parent refused to make the purchase. I did it when I was four or five. I had asked for these monster-shaped erasers at Hallmark. My parents denied the request, so I pocketed a few. The brilliant kid I was decided to play with the erasers in the car on the way home. It ended with me returning the toys, apologizing to the store manager, and a whooping from pops when we got home.
Marcus Peters obviously had a similar experience. He may have been a little wiser than I was and gotten away with it.