One monk that I've met is not allowed to post on Perl-related topics due to his work situation -- because his employer has dibs on his work (this isn't tilly -- it's another highly-respected saint). So he occasionally makes use of Anonymous Monk to reply to a node.

And, as has already been mentioned, the AM also allows a first-time visitor to post without feeling obligated to stick around or even identify themselves. NodeReaper will take care of business if the post is off-topic or objectionable. I think the system works well.

Without the AM, the Monastery would be a poorer place.