I am not sure why some people are staying that hiding menus is the worst thing in the history of the world. A lot of applications have preference / registration based menu items that are shown and hidden as you use the applicaiton. Eg chromes developer menu item.
Those are different applications of the ability to hide the menu item.
The screenshot you posted shows you hiding Export Orders and Clear All Orders. These should not be hidden and shown based on selection, enable/disable is the way to handle those.
A registration menu item can be hidden once the app is registered, and never returned.
Chrome's developer menu is specific to developers, so it's hidden from the average user until it's enabled.
Do you see the difference? If you don't you should brush up on some User Experience basics.