Fair enough, but that argument also works against you:
Why become a cop? He has other interests than being a cop.
is equal to
Why not become a cop? He's interested in being a cop.
Surely you know cops don't eat sleep and breathe law enforcement too, right? As in they have other hobbies and interests? That goes for every job; a tailor has hobbies other than tailoring, and a taxi driver has other interests than driving.
To the best of my recollection the last I've seen bits of traffic data here and there, it's large, but not large in comparison to the US and India.