As usual I ask before spending time looking into it.
Not sure if I know the complete answer to my original question (am I suppose to install and run at the vfhttpd user?), but...
This question was the result of not being able to figure out how run vFabric Web Server as a non root user.
When installing vFabric Web Server stand-alone, not part of vFabric Suite, that user and group are not created before hand. This causes the newserver script to attempt to create them. Which can really only happen if you installed as root.
By creating that user and group first as root, then installing vFabric Web Server as another user, I was able to get things running.