It's a bit of a statement for what you're trying to communicate with that lid - professional experience, political statements, personal "this is neat"...
And part of this is a for me the lid of the laptop is something that I'd need to be able to be comfortable with displaying in front of a CxO without worry about if they may be offended or not (though perl might be offensive to some).
In today's timeline, you'd need to be concerned about what some random TSA agent felt about your stickers and if that might get you pulled aside for additional screening.
I'm not saying either one of them were the deepest of thinkers when choosing the garments for the day, but TSA also isn't employing the deepest of thinkers either, so why poke the hornets' nest
I've heard of similar things before, and had the sense that this was less screeners being dumb and more legislators not fuzz-testing their work.