Actually, it's about the petition software being released on GitHub. Others have made this thread about the unrelated matter of how they dislike the government's use of this software.
If you really want petitions, start a real petition. The website is for something much more informal and you shouldn't get depressed just because 4chan isn't setting policy now.
High-signatory-count means a high level of engagement, among people who were exposed to the message. number of signatures / number of users on the site, or some other measure along those lines.
And the response largely ignored the thrust of the petition. I.e. that the side effects of prohibition are worse than the effects of the substance.
Disagree. 70,000 people signing a petition wanting marijuana legalized does not obligate the government to legalize it. The response they gave contained their view on marijuana legalization and scientific research supporting some of their claims.
All in all, the release of this code was probably for two reasons. 1) The developers liked what they built for the government, and felt that people should be able to use/learn from it. 2) Releasing the code with the readme it has shines a good light on Obama and helps his reelection efforts.