The same way you get Windows without Windows Media Player, IE 8 (in the US), Windows Live Mail, etc.
What programs exactly do you want out of the box from an OS?
Photoshop and iPhoto seem to occupy different aspects of dealing with photographs from my experience with them.
As I have said many times before, I hate bundled software, and I'm not afraid to say I don't care for the bundled crap Microsoft included but at least they give the option of uninstalling some of it now.
I am probably an enigma to Mac users as I can criticize both Microsoft and Apple and not feel guilty for doing so. If you find an Apple user criticising Apple, I wonder if they "strangely disappear". Hmmmmm....