Started out going car-free (mostly because of my inclination/contribution towards a grass-roots, cut-off the cash flow of the "people who would keep us on our knees"), then (when tired of waiting for late buses in sub-freezing weather) remembered that I had a real boat-anchor of a bike. So my first reason was freedom to move (not all that different from when I was 6 ). All the other reasons followed shortly thereafter.

Now: all of the above in no particular order...