Its for the Mac App Store "login at startup" = Open at login

Not sure why the request would be considered unusual. The app is a cloud backup app that monitors folders for changes. If the app crashes the folders are no longer monitored. It is important that the app can be resilient enough to survive a crash, restart and continue monitoring folders. Of course if the end user wants to quit the app it should be able to , but if the app crashes for any reason, like 100 % of app do crash at one point or another, it should have the ability to start again. I am not sure why a sandboxed app would not also have the opportunity to take advantage of toolsets to do this and be against the guides of App Review.