While his treatment does seem heavy handed we have to assume he got very angry when he was stopped getting back to his car which lead to his arrest.
Now lets suppose he DID walk back across the road, misjudged the speed of an approaching car, which swerved to avoid him, hit the central reservation, bouncing back to hit a coach full of holidaymakers.
The coach swerved off the edge of the motorway, down an embankment, killing 15 people on the coach.
Maybe not liklely, but with cars, coaches and lorries hurtling down a motorway at 60 or 70 mph (or more) a mulitple pile up can happen in seconds.
Would he be a hero then ?