How to get rid of Xorg from Macports?
Many ports have a +nox11 variant, which you can add as a default variant in the variants.conf file that's pointed to in your macports.conf file.  However, in my experience, there are some X11-dependent ports that don't have the +nox11 variant. I believe I've also seen situations in which non-X11-dependet port A depends on port B, and port B is so deeply X11-dependent that it wouldn't even make sense for it to have a +nox11 variant. Overall, in my experience, it's practically impossible to keep Xorg from getting installed. :-(