Photoshop replaces art

I wonder now if my street art will be replaced by photoshop.
See, now instead of making art in public, I can sit on my computer and merge 2 photos together to make it look like I did a piece already. And no one but me would really know. Am I wrong?
I mean, 90% of my work leaves no trace anyway. And "no pic, no proof".
I feel that I shouldn't even dare to think such thoughts,
but I consider it a lot lately.
All I really want is a picture, right? That's all I have left. Why not skip the steps in between? Why not just make a picture without making the work. It's way more efficient, safer, makes people happy that I didn't ruin anything, yet I still get to keep my audience.

Now, I need a good rebuttal.