Breaking out the tax is usually a way to make your customers feel the pain of paying that tax. The goal isn't to dupe them by falsely advertising lower prices,

Breaking out the tax is usually a way to make your customers feel the pain of paying that tax. The goal isn't to dupe them by falsely advertising lower prices, it's to get them to support lower taxes on your business. Likewise, it's anti-big-government politicians that want to keep sales tax separate in America.