I have total respect for SAHMs, but most of them I know are also heavily involved in their children's lives - running girl scout troops, organizing food banks, volunteering at their kid's schools, etc. And they will proudly trot out all the things their kids are involved with that they are also a part of, in detailed description, because they made the decision to stay at home for their kids: not for their own personal sake, but for the sake of the children - to sacrifice a second income in order to be a full time parent.
I get what you're saying, but I think it's worth asking what sort of sacrifice we're talking about here. While for some households, the loss of income is relevant, for many it's a wash (especially at the point in their lives when children are entering the picture). The cost of babysitting and day care would consume one of their salaries and cost them time with their children. From an economic standpoint, you can either afford to have someone stay at home (assuming a married couple here), or you can't. If you can, then I don't see how that choice is any different regardless of how much above the point of being able to afford it you are.
From a self-reliance point of view (being a breadwinner), there's a different sort of sacrifice. This is where the whole women's lib type of argument comes in. Sometimes, it's not about the money, but about the sense that one is providing for themselves (and their family). But that choice/goal/whatever is not (or should not) be considered any better or worse than the decision to stay at home and raise a family. Which kinda brings us to the issue here. That choice is no less a sacrifice for Anne Romney as it is for any woman in a similar situation. It's just not all about the money IMO.
Ann Romney got the luxury of it not really being a sacrifice.
Again, I disagree. Unless one completely discounts an element of sacrifice which I suspect a whole lot of women (especially liberal women) would think is a big deal. Regardless of how much her husband makes, a woman is sacrificing something by choosing not to embark upon a career of her own. This is part of why I think this thing has struck such a cord with so many people. The heart of the statement makes an assumption that is completely counter to a century or so of women's right arguments. It assumes, in a backhanded way, that a woman who can be supported financially by her husband has no intrinsic reason or need to work and should not feel like she's missing anything by not doing so.
Again, I suspect a whole lot of women's rights activists would take exception to that assumption. The only reason this isn't being much more loudly condemned by those groups is because of politics. If Romney were a Democrat, you can bet the outrage would be 10 times as loud.