In System 7, the function of the Backgrounder is built into the Finder. You don't need the Backgrounder file at all if you're running System 7.
The Backgrounder file is, however, required on System 6.0.x systems that use System 7 printer drivers if they are to do background printing.
When you run the Installer on the 7.0 Printing Tools Disk from a 6.0.x system, the Backgrounder on that disk is installed on the 6.0.x system.