You could make the same argument for sports- most children who interact in sports will not do so professionally. There are physical/mental benefits to sports which at the end of the day 'doesn't matter'.
I feel that the purpose of making your child learn X at a young age is to simply expose your child the possibilities of life. There are so many overlapping ideas or life skills between different disciplines that any experience is good experience. Of course, like the answer to many things in life, moderation is the key.