Why not include persuasive evidence of the value of having chickens?
- Bug Control, Could -- over time -- reduce city expenses if they currently spray "as needed" for pests (not sure if they do that there, here it is common practice for mosquitos)
- Family Enrichment (Chicken keeping teaches children responsibility, strengthens familial bonds when chores are done together, etc.)
- Community Health (Go to Mother Earth News and Print out their study on the health benefits of pastured eggs)
- Community Ties (Those who have extra eggs could share locally helping to forge and strengthen community relationships that could lead to lower crime rates, fewer civil disputes, etc.)
- They could help set "Environmental Bar" in the USA and be seen as a Pioneer community for overturning their legislature, this could lead to increased press, and greater revenue for local businesses via tourism
- More money will be fed into the local economy both with people buying feed, supplies, etc. and you could even argue that money saved and the community ties formed will encourage people to extend their local way of life to other arenas, keeping local businesses open.
And I'm sure if you put more than the 2 minutes of thought into it I did here you could come up with many, many more arguments to make your case! Let us know how it comes out!