For nuisance apps that set a badge notification icon, but which are not in the Settings Notifications center, is there a way to block the badge icon?
Spotify, for example, creates a notification for every insignificant event, with no way of blocking it in app.
Personally I don't understand how apps are allowed to show a badge icon without being in the Notifications center in the first place.
Example:
Best Answer
I have a solution that I was able to reverse engineer. I've tested it on my machine, running Yosemite 10.10.4 (14E46). If you can find the bundle ID (in the Info.plist file for the app bundle), you can use this script to force the app to appear in the notifications preferences pane.
At this point you can open System Preferences -> Notifications, and you will find the app that you just added at the bottom of the list. You can enable / disable badging the icon from this page.