@vfx: Sounds like it's still in the planning stage. I'm always happy to see business owners exercise their freedom to set prices in a competitive market. I don't think that SUV-owners are a protected class, so as long as their pricing policy is clearly posted, I'm all for this.
There's even a general reasonableness about the approach, from a cost perspective: as the photo accompanying the article points out, there's a correlation between vehicle size and energy consumption. In a postage-stamp-sized parking lot like this, I'm sure that space is at a premium, and parking an F350 or an H2 may cause problems.