Just to play devil's advocate, let me ask this: is it possible their insurance company requires them to display the sign? Just a thought.
Other than that, how can you be a liberal tree-huggin' anti-gun hippie, and still make products for high performance cars? That's like owning Exxon-Mobil stock and being an activist in GreenPeace.
What I would personally like to see is a picture of the place, with the sign clearly shown. It's not that I don't believe you, but I want to see it for myself (where it is, etc.).