I noticed that near the end of the show's run (Season 7) that during the credits an extra scene was shown; some looked like outtakes, deleted scenes...

Were these made especially for the credits? Were these outtakes? Why was this done?

I don't know for sure, however I would think that these were filmed specifically for the closing credits. They aren't outtakes, I'm sure of that. A lot of shows during that time introduced scenes during the closing credits. Roseanne comes to my mind right away. Maybe the producers just decided to throw this into the mix. Plus it was the final season, maybe they were just trying to have fun with it.