It would be nice if there was an option next to apparel so people could choose if they want to hide an apparel or not when the wolf is in campaign or arena. I have some backgrounds attached to my wolves, so I never choose them for these activities because the background sticking out is too ugly/weird.
To add an option to hide all backgrounds would be great, but what about the foregrounds that are meant to go with the background? Those will be sticking out too, and besides it's going to give too much work for moderators to decide if something is a background or not. So why not just turn and apparel off manually?