You can go to ground in them if traversing treeless terrain....similar to a bivi bag & tarp/ solo tent setup. Obviously not as comfy. You just have to plan ahead.
Add a pad & sheet for ground insulation & use your walking poles for hanging the tarp & for keeping the sewn in bugnet out of your face.
It's doable. Depends on how hardcore a hammocker you are.
I've hung from rocky summits, overhangs, caves, under bridges, single tree to car/motorcycle etc etc but I've also gone to ground ( no other choice) in sandy treeless desert nation parks....you just have get flexible & creative.
On exposed terrain with frieght train winds or horizontal rain...occasionally, easier & safer to take a tent. Heresy, I know.