It seems to me that about 10-15 years ago, laptop stickers were a little more like patches on a punk jacket; that is, they were meant to show something about the cons or competitions you have participated in. A few such places would give out stickers.

At some point, people saw the cool-looking stickered-up laptops and thought they would also look cool and put fun stickers on their laptops to show that they also can google things. This diluted the original social signal value until it was completely ubiquitous, kind of like if everyone started putting whatever patches appeal to them on whatever jacket they wear without any thought to the idea of their origin. By that time, the original sticker-signalers had all moved on to other signals.