Seriously though Miss Marple, why would you protest and march?
The Garden Centre land is already a commercial property. It's not in a residential, or even semi-residential area. And a decent sized supermarket getting being built down there, would help the arguments against one on Hibbert Lane - in fact, Asda (or others for that matter) might even think twice about going ahead with trying to get Hibbert Lane, as a supermarket down on Otterspool would almost certainly be built, opened, and thriving before the dust settles on he initial planning application, nevermind the end appeals, calls for public inquires, etc, that are bound to be associated with any move on Hibbert Lane.