On the edge of the seat

I have been asking this question for a long time. Dont get hyped up. I have been wondering why Auto-walas always sit on the the edge (or corner) of the seat while driving.

Some of the possible reasons i could think of are:

1. The auto-wala himself is very curious to know wat will happen next.
2. To make those zig-zag turns easily (when you least expect)
3. To run away in a jiffy if he gets caught by a cop.
4. Not too interested in padhavi (position / seat)
5. To accomodate another passenger besides him.

I have used a masculine term for auto drivers since i have not seen a lady driver sit on the edge / corner of a seat while driving.