I openly don't (and I can't stand the narcissism that is involved in the reason). If you look at the parenting most parents do, they do it as if the child should be like them, just smarter or achieve more - but otherwise similar (as I said: narcissism).
On the other, here is an article (that has been brought up on HN some times in the past) about the life of a super-smart - it is easy to imagine how the life of the parents would be:
> http://www.worlddreambank.org/O/OUTSIDRS.HTM
(BTW: If you look in the German Google News about "Höchstbegabung" (the German word meaning that your talent (in this case IQ) is at least 3 sigma above the average; FYI: "Hochbegabung" means 2 sigma above average) you will find more news about soccer than about "Höchstbegabung" in the sense of intelligence. This says a lot about the society, IMHO).
Evolution at work. Parents who tried to make their kids different than themselves did not raise parents.
I don't think "that should be fine". In the third world people are poor and produce children. Simply stopping doing so would be a fast way to reduce poverty (in my opinion even a necessity).
I was one of those gifted children; both my parents are extraordinarily smart and I was years ahead of my peers in reading and maths. I'm happy no-one paid much attention and I was left to my own devices. Maybe I didn't become a billionaire, or go to Stanford at sixteen, yet I was mostly happy, most of my life, and every time I accomplished anything I was grateful and happily surprised. And I don't think it was a wasted life at all.
Leading society? What an arrogance. Let kids be, give them open access to knowledge and freedom to learn from others, and structure where they need it. Leave the "raising geniuses" to totalitarian regimes.
The whole trick is in instilling such motivation in gifted children instead of the opposite message.