/usr/local/www a tradition?

[Modulok]

Is there a compelling reason for placing subversion and web-server
data in /usr/local and not somewhere else? I was thinking of keeping
all user accounts (human and daemon alike) in one place like,
/home/www and /home/svn and so forth.

Before I break convention, I just thought I'd see if placing said
files in /usr/local was just a tradition or if there was another
reason for it.

Thanks.
-Modulok-