Running Mac OS 8.0, the behavior when dropping a suitcase containing a desk accessory on top of the System Folder has changed.
Under Mac OS 8.0, if you drop a desk accessory suitcase on top of the System Folder the entire suitcase will automatically move to the Apple Menu Items folder. With System 7.5 and Mac OS 7.6 the desk accessory was removed from the suitcase and put in the Apple Menu Items folder, and the suitcase was deleted.
The change was not intentional; a future release of the system software will likely change this behavior.