Hello,
I mean I have played a couple of MMOs where seasonal events were a good way for newcomers to make some good fortune. In FFXIV it would mean that the lucky eggs would have for example a small (but not relic quest small) chance of dropping materias and expensive materials.

I know that it would change prices of materials and materias for a few weeks but then the prices would return to normal, so there will be no permanent harm to economics but the events will be more profitable and will live longer than day or two (because now people get their rewards and mostly don't bother wasting their time for a few allagan pieces).