Remember, there are different sorts of gifted. Highly creative, highly intellectual, highly academic. Sometimes kids have all of those, one, two or other gifts altogether.
I read recently an article in the NAGC quarterly about the difference between kids who master and those who create. Both kinds are gifted in their own right, however, they may present differently, especially in school.
I think we find it easier to support the child who is clearly academically gifted.
I've mentioned before that having read about Einstein he seems to fit more in the creator gifted category. Didn't perform as well in school as would be expected. However, he seems to be the most obvious symbol for genius.
And then of course there is Richard Feynman.