Imagine a, say, Star Trek episode that is set on some planet we don't know with some species we don't know, where some characters we don't know occasionally mention Star Fleet and The Federation, but are mostly just doing their jobs and concerned with their own issues. At the end of the episode, they've had a dramatic arc in their relationship and -- oh yeah -- in the middle, they finished that work-thing as an incidental. At the end of the episode, we see the cast we know on the starship we know and final shot closes in to emphasize that the work-thing is on board. We didn't NEED to know the backstory of the people that worked on the thing, and their story doesn't matter at all for using the work-thing, but the audience has a deeper view of the show's universe.

Is that sort of show filler, bridge, or neither?

Edit: Dr. Who's Love and Monsters was a little like what I mean, but that had more Doctor than my hypothetical would allow.