If your software is free and the maintainers aren't getting paid then a few Easter eggs are a small price to pay.

Colin was being paid, of course, but not primarily for maintaining man.

Having said that, I once worked at a company (incidentally one where Colin worked, though after he'd left to join Ubuntu) where a developer added a line to the T&Cs that meant that a user granted their soul to the company. The intention was to check if the execs/legals checked the T&Cs like they promised to. They did not. Many souls were captured.