I'm about 90% sure that Adobe makes their software very easy to pirate in order to keep their monopoly. For CS4 and CS5 there were no cracks to install, just map the sites it uses to call home to localhost and enter a fake serial number. You could even run the updates. They could have very easily disabled this in an update, but they never did.

Businesses will still pay for it, and there isn't much room for competition in the individual/very small business/student market because it's hard to compete with free.

No one's really clamoring for a reasonably priced alternative b/c it's basically free.