Gamma correction is not just for CRT monitors, its for everything that prints or displays color images. Having spent many afternoons calibrating huge $15,000 large format printers in ad agencies and art departments, GC is crucial for not only PCs and MACs but for printing equipment and even the presses that print the Sunday supplements in newspapers. If the ad for Acme Soup in the Sunday supplement has a can with colors that are slightly off, then the client is slightly outraged and you've only slightly broken your contract.