Not everyone has that luxury (although camera manufacturers should get their head's out of their asses and include this feature in every camera).
I filmed handrails all winter long under shitty, halogen work lights. They give off a NASTY yellow/orange look to the human eye. All I had to do what wait until the sun is all the way dark outside (or else the sky/area not under artificial light is a nasty blue), white balance off of the lit up snow, and everything looked proper.
The worst shooting situation is when there are various temperatures of light everywhere and you have to balance to one of them. This results in terrible tints all in the other ranges of temperature.
White balancing can suck.
"it sucks knowing your dick is longer than the base depth at your local mountain." -bailiff