Maybe Altium would be better off spending the money on making a secure app if they are worried about piracy.
I'll be the first to admit I have used pirated software, mainly due to the fact I wanted to work at home on some things that we have a license for in work, and I am not ashamed to admit to making some of these applications "work" when they are not available elsewhere.
Without going into too much detail, to make Altium 14.3.14 "work" for example, you change 1, yes 1, byte in a file.
And it has been the same for a while now, I mean you don't get access to the vault etc, but you have to admit they are not doing much to prevent piracy!
And as people have mentioned, the change from version 6 to 14 for example is negligible, so chances are the old software will work fine if they do decide to use OTA activation techniques.
Look at the likes of Eagle or Diptrace, yes they get "fixed" but rarely do you need the features of the full version for hobby stuff, for those who use Altium day to day and want to design something at home, they have no real option to either use a pirated copy or use a different package.
Something as simple as releasing a free version might cut down a lot of the piracy as Altium is seen as "industry de facto" people want it, and for all it's quirks it does work, I use Eagle and Altium primarily (at work, yes, licensed).