Ah, you work in academia.
Nice try. But actually, think non-academic (though Ph.D. filled) biomedical-type private, staid, serious lab environment with scientists who don't go in for the overt "geek == games == internet == star wars posters" ethos. Not up on the internet geek memes. Generally older, wife, kids, watch sports/BBQ on the weekends, not "social rejects" at all. But as scientists they look at these cartoons and say "how true."
That said, I'll be the first to admit to the percentage of meme-driven XKCDs that aren't that funny to me. But being hit-or-miss is a sign of originality, not the obverse, when the hits are true hits.