I'm guessing most people do it either because of security or for deployment into non-wordpress situations (e.g., you can basically host your small blog/site for

I'm guessing most people do it either because of security or for deployment into non-wordpress situations (e.g., you can basically host your small blog/site for free in App Engine). For infrequently updated sites where there aren't multiple authors, wordpress is overkill and not worth the security concerns, IMO.