Ask Apple, that was their strategy for the last 3 years to make ppl pay a few hundred bucks more for added phone functionality and camera module. iPod touch 3rd gen and iPhone 3GS were the best example of this policy. Same screen, same parts (well 3GS had a little better speaker), and 200-400$ price difference (depending on the capacity) for just a GSM module and a camera.
No, I'm asking you. What makes you think you DESERVE all the thing the iP4 have but without the high price?