I see people frequently claiming that Adobe's policies are driven strictly to generate new sales but when challenged they can never explain how Adobe should backfit new features like Content Aware fill and Healing, Puppet Warp, the new Quick Selection brush, Lens Correction, etc. into the old versions of Photoshop.
I think most of the gripes (that I see anyway) are about older versions of ACR not supporting newer cameras. As I said in my post, if they were doing it do drive sales then they would not offer the free dng converter, which Adobe does update to include newer cameras. I don't know the nuts & bolts of the RAW format, but I'd be happy to have the converter if/when I upgrade my camera and CS5 won't support it. Just my .02, but I think it's great that Adobe updates the converter for free.
Hopefully, nobody expects a one-time buy and then a forever upgrade with all the new bells & whistles . To me, the upgrade price isn't that bad and I haven't minded putting the $$ for the improvements and new features. I'd guess that Adobe loses quite a bit of revenue each year to Educational use abuse, not to mention hacked copies.
I will say that Topaz has upgraded most of their plugins a couple of times for free though. While most of it seems to be gui oriented and behind the scenes stuff, it is still appreciated.