You know Photoshop is not only used by graphic designers. I am sure the rest of us are not using it to its full awesome potential. And I was asking around here about GIMP not Photoshop. And we are talking about Photoshop not the CS which the average person doesn't even know about or want.
So it may be true that none of your clients ask if you use photoshop, mine do and everyone else I know also. But again I am not a graphic designer.
I am just a little bit more than the average Joe. I am not a computer, graphics, or engineer wiz. I don't have and friends that work at Adobe or that create programs that I use. I will go out on a limb and say the average person doesn't either, not even the professionals that use this stuff. I also don't have the time or patience to learn a bunch of different software packages just for the heck of it, especially when I will never use them. Why would a person do that anyway?