It makes sense that if you delete/uninstall an app, then there is no way for that app to continue to use your location data - if for no other reason than that app no longer exists on your iPhone.
Did you register at that dating site, through the dating app that you mentioned on another thread?
You might go to that dating site, and see what you need to do to remove, or close your user account at that dating website.
That may not be necessary, but you might contact that site with your questions.