?

The raindance is just one of the little island activities that the villagers do, just like laundry, telling a story or teaching!
Having them do one of these actions may not affect something directly, but they sure can be fun to watch!

All that work on the table, all the techs in spirituality, the idol and everything else, and these ppl can't even "raindance" for real?

Maybe it's their lack of full faith...