Besides 1-time activities (quests, 1st completes, etc - which cannot be repeated), there is no gil generation in this game that doesn't incur a repair loss greater than the gil introduction.

If you think there isn't a gil problem, it's because you aren't 50 and running endgame content yet. Repairs are draining me faster than I can believe. There is almost NO gil introduction once you have done the one-time content, and the gil removal goes up to a ridiculous degree at endgame.