Being white, distracted and in a tourist spot at 10pm on a Saturday nite is NOT a motive.
A motive would be that the perp wanted to rob him (which obviously didn't happen), or was a psycho killer (possibly one who hates Pokemon?), or someone who had a personal beef with him, or some leftist anti-white political whacko wanting to kill whitey.
True, it's not wise to walk around in public completely distracted, but in and of itself, the most you can say is that doing so presents an opportunity for criminal attack. But in and of itself it cannot be a motive.
You don't need 'political' to describe this. We've all see the hate that is out there in the underbrush of society for vulnerable white herd gazelles in dangerous places.