There are worse things they could mandate eh? To be honest, I'd rather live in a place that mandates gun ownership, rather than one that tries to remove guns (like say...Chicago and NYC). Kennesaw, GA has had their mandatory law on the books since 1982 as the article says, and they haven't enforced it, but crime rates dropped sharply after it was enacted, and still remain lower than the surrounding suburbs of Atlanta.
It's already been proven that gun owning, law abiding citizenship leads to less crime.
Just because they pass a law mandating it, doesn't mean they have to enforce it. If it's a well known law on the books for said town, it works in their favor.