First Of All, Why Even Create A Google+ Business Page?
The main reason being visibility in organic search or Search Engine Optimisation (SEO).
When logged into Google (via Gmail, Adwords etc.), Google incorporates information from the people & businesses you have connections with through your Google+ profile and returns more personalized search results including pages, posts, images and profiles of people you are following.
You also have the ability to discover people related to your search beyond immediate connections.
This search personalization is called Search, Plus Your World.