Why does Mothra have fairies?
What's their purpose?
https://www.youtube.com/watch?v=63laClz1Ixg
It was a tie-in at the time with The Peanuts (who played them) as they were a popular international singing group at the time. Therefore the purpose (as is usually the answer to any question anyone has about filmmaking) is "to make money"?
shareOkay, I didn't know they were famous in their own right.
https://en.wikipedia.org/wiki/The_Peanuts#:~:text=The%20Peanuts%20(%E3%82%B6%E3%83%BB%E3%83%94%E3%83%BC%E3%83%8A%E3%83%83%E3%83%84%2C,%E4%BC%8A%E8%97%A4%E3%83%A6%E3%83%9F%2C%20It%C5%8D%20Yumi).
However, I wouldn't say it's all about money. It adds a creative angle to the film. The fairies are nice!