If they have to 'go', just make it easy to disable (or make them all "up down left right a b select start").

That said, even Microsoft Office has easter eggs -- http://www.howtogeek.com/howto/microsoft-office/fun-at-work-microsoft-word-easter-egg/ -- And I actually had a coworker freak out when he did that (he was trying to document some code, we ended up going for 'foobar = rand()' and that stopped it). Everything has easter eggs and they're easier to trip when you're a newbie than any other time (unless you're a bored bank worker stuck in the office on Christmas day....)

I don't see it as unprofessional at all. And I bet that guy never makes the same mistake again. AND the tech has a great story to win drinks with at the bar.