I think the requirement for animals to sleep is an evolutionary device, which ensures that the body has time to regenerate and heal itself at a more intense level than it would were it awake and moving. Ever notice how you can feel sick all day long, but often times upon waking the problem has completely disappeared? Emotional stress is also lightened considerably after even a moderate amount of sleep.

If there were a way to "deactivate" the need for sleep for life, rest assured our average lifespans would be shortened considerably, and our health problems would mount to the sky (more than they already have).