working two part-time jobs (say, one at Wal-Mart and one waiting tables) without benefits because you can't get a full-time job offering a single ten-hour shift. On top of that, you have to find child care, get to different places on time (but your car is acting up or the bus schedule makes it difficult), and deal with a medical problem you can't afford to fix. There's barely time to help your kids with homework, let alone ferry them to after-school enrichment programs that you can't afford anyway.
I think it's easy to lose perspective when you don't have to face these kinds of circumstances.
It's also easy to assume that lower-income people have low IQs and that their kids wouldn't get much out of the Russian Math School anyway. I recently spent some time with a large group of PG people, and they weren't all in a position to afford expensive extras. Being PG is no guarantee of earning a high income (it may work against it, in fact).
Well said. Giftedness and opportunity are two
different things. Withholding appropriate academic instruction/stimulation from children* may lead to underachievement, brain-based changes, and pronounced lack of opportunity. Each child benefits from an education which "fits" their present state of development: A good fit does not restrict but offers a bit of room and flexibility for movement, stretching, and growth.
* Side note: Some parents may do this either intentionally or unintentionally (neglect to read to or talk with children; not understanding parenting; not addressing child's questions; not encouraging curiosity; not understanding typical development vs gifted; understanding giftedness to a degree but not wanting child to be gifted or stand out; not wanting to allow younger sibling to surpass older sibling; not wanting to allow child to surpass parents, etc.) Some schools may do this by benign neglect of the gifted or by trying to close the achievement gap or excellence gap by capping achievement of gifted and/or high-achieving pupils. Some in the gifted community may do this by artificially treating the number of seats in gifted programs or services as a finite, limited number to be competed over; by making psychologically damaging comments about high or low SES or cultural preference for hot-housing. At some point it would be lovely to have all children learning and growing academically/intellectually/emotionally. 
