There should be no tax relief, or if there is it should be limited. 3K per kid without limit, you can birth yourself out of taxes. If your contention is that you have to have these tax breaks to raise children, then maybe that says that the overall tax rate is too high.
Why is it that a lot of resistance to the "pay your own way" doctrine comes from the very same people who argue the rich should keep more of their money? They earned it, they should keep it right? Well I earn mine too, why do I need to pay for you? Also, minimum wage should be abolished.
Well, I think that we have to recognize that, responsibly or otherwise, the tax code has been used (abused) in a social engineering kind of way. Whether via incentives to promote behaviors (saving for retirement, purchasing hybrid vehicles) or via disincentives to disincentivize other behaviors (smoking, energy use). Hence, it's not surprising to recognize that the tax code then provides tax incentives for having children and provides tax advantages for married couples. These incentives/advantages reflect what, imo, is a compelling interest to the State - promoting marriage and procreation.
Now, I'm not sure what you mean by the pay your own way doctrine, though I am presuming that you're referring to resistance to government actions repealing these benefits or advantages. As such, I see no hypocrisy. The resistance ain't to paying your own way but a resistance to the federal government choosing to no longer incentivize marriage and procreation. Like me, they recognize a compelling interest for the government to encourage the existence of our society rather than adopting a national suicide pact as it discourages the regeneration of our own society.
Reproductive rates are so bad among western nations that one, Japan, is now directing employers to permit workers to leave work early in order to encourage sexual activity and reproduction. Western nations, and the US is on the borderline, are for the most part in negative replacement right now. In other words, unlike the US where birth rates per woman hover just above 2 per, you see elss than 2 across the Europe. Hell, even China is facing a similar birth dearth. Meanwhile, Muslims nations, African nations, and most Latin American nations are reproducing like rats. There's a strategic issue there that very few people are paying attention to.
It's also why they, like me, would argue that granting unprecedent access to terrorists and unlawful combatants and not permitting our intelligence services to use physically coervice interrogation techniques because we may offend Russia, China, Sudan, Iran, North Korea is simply signing a national suicide pact. Doing so virtually guarantees we won't be able to defend ourselves.