With respect, this shows really poor judgement. Call it bump, collision, crash, whatever; if there'd been people involved there would have been injuries — likely severe (drone props at head level) — no matter how fast the aircraft was moving and no matter how big it is. Walk face-first into the props sometime and tell me I'm wrong.
If "reasonable precautions" don't include the possibility of running into a car (or two, at low altitude in a parking lot no less), then they're worthless. It's your responsibility to ensure that your actions don't put people OR property at risk, so yes: you are wrong on that.
I appreciate the thrill of putting these things through their paces; we've all been there. I'd hope most operators would try new things out in areas where the only damage potential is to themselves or their aircraft.
For what it's worth, I'd advise you to pull that video entirely and find a local operator to show you the ropes.