I'm also dubious that GitHub is the right way to release data. There are a huge number of people interested in civic data, and GitHub is probably one of the least accessible ways for 99.9% of people to get it.
For example, a number of city and regional councils in New Zealand publish their data via Koordinates.com. Wellington City Council alone publishes over 50 key datasets:
http://koordinates.com/maps/wcc/layers/
(disclosure: I work for Koordinates)