I've always thought photoshop was made intentionally easy to pirate, as an unfair competitive advantage to keep other companies out of the market (companies and serious professionals buy it--everyone else pirates it).
CS5 didn't even require a crack, you just have install the trial version with a fake serial and edit your hosts file to stop it calling home.
Maybe it is relatively easy to crack compared with games, but non programmers like me don't even know what host files are. That being said, if it is relatively easy to crack you are probably right. It would be financial suicide to compete with them since you couldn't limp in with a weak program. Great point.
CS5 didn't even require a crack, you just have install the trial version with a fake serial and edit your hosts file to stop it calling home.