I think you're seriously underestimating Wine, and the amount of 'real' work it can accomplish. The world doesn't revolve around Adobe products, contrary to what many recent converts to GNU/Linux may think.
As usual, I am not talking about myself, but people in generals' perception of it, which reflected quite well in Shuttleworths comments. Whatever you think of the guy, remember he was a developer on the Debian project in the nineties. He's not totally unitiated. And I don't think he is unique in any way.
Also, (quoting http://www.winehq.org/about/): "Wine is still under development, and it is not yet suitable for general use." Doesn't say stability. Especially when the version has passed 1.0.
And the *rest* of the world DO revolve around a few applications. That is why they think so.
Though, I must say, the majority of people I see/hear using Photoshop *are* using it as a toy/hobby, not for 'real' work, i.e., a full time job.
I have the same impression. And most haven't paid for it either. Anyway, that really isn't important. The important thing is that they want it, no why.