If apples "OS Updates" for Mac OSX contained anything more than slight graphical tweaks id be happy to pay more...the OS upgrades are about the ONLY thing apple price realistically for what they contain.
Apple's OS updates do contain a lot more than "slightly graphical tweaks". Parallels updates: not so much. And the price argument; it's very outdated.. the macbook airs for example have been cheapest in their range for a while. I wasn't even able to get a 27inch all in one for a while other than the iMac, and the iPhone: well.. they could make it out of plastic i guess...?
But, ok, you think 50 a year is perfectly fine, i don't. I think they're rip-offs.