Openbox overhead is similar to that with gnome-panel

I just installed openbox via sudo apt-get install openbox. It already has obconf, btw.

I noticed that when I logged into my openbox session instead of the one I usually use (gnome-panel and NOT Ubuntu 2D or one of the high overhead environments) and checked via htop, I found that a similar amount of RAM was being occupied (~600 MB or so) with openbox or gnome-panel.

What gives? Openbox looks lighter but it certainly isn't any different. Obviously the same daemons etc would run in both environments as they share the same folders.

Is gnome-panel as good as openbox then?

Edit:

The comparison of memory used is quite similar and the gain isn't large by any means (by using openbox) htop output with gnome-panel

htop output with openbox session