Learning a language is a commitment. It takes years to become truly proficient, and even then there will be yet more to learn. (I'm still learning new words and cultural references in English, and I've been speaking it since I was in diapers.)
Raising global children does not have to cost much money, nor does it require hundreds of hours of free time. The single most important part of raising global children is to instill in them the right attitude.
What would you do if you could give your child something that is proven to boost her creativity, empathy and cognitive functions, while putting her on a path to increased academic and career success? You'd jump all over it, right?