It was a robbery. It had none of the elements of the knockout game, beyond the surprise punch. He didn’t do it for entertainment. He didn’t video it, or have an accomplice video it. He didn’t laugh, or taunt his victim. He punched her, robbed the store, and left.
I’ll put it to you this way then... Why do blacks feel the need, and it is a quite recent need, to go around punching out White people?