Emptying out Photostream on iPhone with computer?

So heres a question for ya...

Say I take a picture on my iPhone and it gets uploaded to the photostream. I view it on my computer in the photostream folder. If I delete that photo from the photostream folder on my computer, shouldnt it be deleted from my iPhone too?

It just seems weird that Apple makes iCloud have the idea of being able to sync in real-time with all of your devices but as soon as you want to delete something from the photostream, you cant.