what Bud, and CEM said +
heel strike in a shoe, has little to do with your needs for a footbed in your ski boot. the majority of the human race wears out the shoe from heel strike. pronated, supinated, or neutral, your shoes will wear from the outside heel of the sole.
a well made footbed built for ski boots will tend toward being accomodative under the foot which gives great comfort and basically brings the snow into contact with the bottom of the foot.