What you're describing as "fluff work" is actually a critical task in any business. My own boss breaks down our work into two categories "new development" (exciting projects everyone wants a piece of), or "keeping the lights on". Fluff work falls into the second category (such as creating domain classes for all those all programs that read data using SQL statements instead of ORM's).
Ideally, the systems would be so well written and robust that there wouldn't be a large amount of such maintenance going on, but the reality is usually a little more dour.
Ideally, everyone would pitch in, or at the very least the manager would assign that work equitably. If that's not the case, the the problem is not so much the existence of fluff work, but the way the team is run.
As to how to handle it? Do the work. Share the work. Keep the lights on.
If no one else is pitching in, it shouldn't bother you. Just keep working on "fluff" at your own pace, and let the chips fall where they may. If you find yourself becoming the designated "fluff guy", tell your boss that you'd like to work on other projects more often.
Do keep in mind that often times the reward for a job well done is more work.