Consider the risk involved in Apple, Dell, Compaq. This is where we have to consider with the huge profits. Also involved are development fee at the initial phase of these business.
The cost nature of an principally intellectual business is very different from manufacturing business. In an intellectual business, the overhead, the equivalent of "factory" is extremely high compare to the "variable cost". If you measure into the risk and amortization of the intellectual property, perhaps the profit will not be so high.