If this were a real bumper sticker, I’d take it out to the parking lot of my apartment building, and apply it OVER the one this one truck has that looks just like it.

Have you ever noticed people don’t notice small details have changed until they start piling up? I once played a prank on my friend where I would hide a small rubber duck in his house everytime I visited him. Small like the size of your fingernail. I got to 50+ hidden before he noticed one.

So my thought is, it would be weeks or months of him driving around before he noticed. He may never notice.