EmacsWiki does not require users to UseRealNames. If you look at the list of homepages, however, you'll note that most of the names seem non-ridiculous:
AlexSchroeder, JohnWiegley, FrankGerhardt, DanielLundin, CharlesSebold, TobyHaynes, AaronL, DeepakGoel, MarceloToledo, JohnPaulWallington, ...
I doubt that the Emacs community is more business-like. The Emacs community is probably just more interested in Emacs than in fooling around (without Emacs). This is why the Emacs newsgroups [1] have a very high signal to noise ratio. Another interesting fact is that most regular contributors to the wiki got there because they first heard about it on #emacs. And PenName""s are very common on #emacs:
Users on #emacs: ged @kensanata neogenen_ termos johnix @franl @delYsid giuppi delta_ vorpal enberg PurpleHaze jamc_ skimpIzu bpt Lennart mallum pflanze ...
Possible explanations:
Obviously EmacsWiki does not require a UseRealNames-policy at the moment.
It pains me to add threadmode to this clean page, but an interesting concept is raised: "non-ridiculous names".