Because of your eye's sensitivity to different frequencies, the "warmer" colors require more energy for the same effective lighting. Hence, highway departments choose the "daylight" option to save energy.

I'm sure the LED manufacturers will take full advantage of this opportunity to create "true-light healthy LEDs", for which they can charge double or triple.

You can already get some (actually really nice) LEDs for your house that change color to lower temperature (more orange/red) as they dim, mimicking the effect of dimming incandescents. It does make for a nice cozy atmosphere. As you say, they're not cheap, but I'd consider them strongly if I were redecorating.

Edit: it's confusing that a cool blue light is a high temperature, and a warm orange light is a low temperature.