From the AppleCare Knowledge Base Article ID 60726:"Package First Aid is a utility that resets folders that have been incorrectly configured as application packages. If you have a package or folder that cannot be opened, drag it on this utility to reset it as a folder. Do not drag application packages on this utility." Personally, my Package has never needed First Aid, but if it has happened to you, join in the discussion below!
Thanks again for the idea, Chris Argiropoulos!