if you want to run "hosted" mode, where the javascript and java is executed by eclipse, then yes, GWT requires eclipse.
GWT itself does not have a "desktop" mode, it does not have a "desktop" version, and so GWT apps cannot themselves be run as a "desktop" app unless you use the GWT Eclipse-basesd "hosted" mode - or you run the GWT-compiled javascript under Adobe AIR, Mozilla's Gecko / Spidermonkey, etc. etc. etc.
Right yes I don't think GWT is really interested in desktop - unless like you say you compile it, but then its quite different.
I have run it hosted just fine with no eclipse components (only for dev of course) - just the JVM and about 10 meg of jars (or 9 meg dev jar) - I am not sure where you get the 150 meg from though?
GWT itself does not have a "desktop" mode, it does not have a "desktop" version, and so GWT apps cannot themselves be run as a "desktop" app unless you use the GWT Eclipse-basesd "hosted" mode - or you run the GWT-compiled javascript under Adobe AIR, Mozilla's Gecko / Spidermonkey, etc. etc. etc.