well, the fact remains that installing the Aqua bits for the Gimp uses all of 196k of disk space: is there any compelling reason *not* to install it by default? 

[/Applications/MacPorts]# du -sk Gimp.app/

196     Gimp.app/

Especially when you consider that, deep in the bowels of all that stuff, you find a script[*] that simply runs the command-line app.