It's easy to pick on Apple in isolation. When you compare Apple's practices to other big vendors they're not all that different. Dell charges a tiny fortune for memory, especially for server models, compared to a wholesaler, they need to protect their bottom line as much as Apple and upgrades are always how they make their margins.

I'd rather that Apple deprecates older models of hardware than insists on supporting them perpetually. I say this as a developer. If you make an app for 10.7 you will not have to worry about building a PowerPC version, about testing it on a 2005-vintage Mac Mini just because one of your customers might have one. It's not supported. Period.

I know several people that are perfectly happy with an older system, 10.4 or 10.5 vintage either out of necessity or out of indifference. It works for them and they see no urgent reason to upgrade.

How much garbage do you think there is in Windows to support devices that haven't even been manufactured in the last ten years? How much better would Windows be if they abandoned all that and focused on making it better? I think it would look a lot like Windows 8, actually. Faster all around.