Some people rationalize it with that making sure their kid lives in a nice house in a nice neighborhood, goes to a great school, has access to all the latest gadgets and gets to to travel the world is the best thing they can do for their kids. And if the cost is that they have to work 14 hour days and hardly ever see their kids then that is a sacrifice they're willing to step up and make.
No saying I agree, but I can certainly see how you could convince yourself that working an 80 hour week is you doing the best thing for your kids and family.
Furthermore while I agree with (having done so myself) saying "Take a pay cut, do less hours.", it is only easy when you are already essentially rich. If "take a pay cut" meant I would have to move my family into a tiny apartment in the shitty part of town I probably wouldn't have such a cavalier attitude about it.