The traditional right wheel drive has been introduced in India by the British which is still in existence.
So the vehicles are bound to drive left on the streets.

An auto driver who always tries to maximize his profits tends to allow either one or two passengers sitting next to him. A passenger would preferentially sit to the left of the driver marking himself safe from the faster traffic on the right lanes, this made auto drivers sit slightly to the right to make space for the ones sitting next to him. This must've got into the skeletal systems of them over time😂😂.

Secondly, when it rains the wiper usually doesn't wipe way too higher for the driver to look through, hence they tend to move a little to their right making it easier for them to watch the road. 
-Supreet