I know its just a bug but I found a use for these dwellers if you have a shelter with a zig-zag room strategy for some of your rooms. I use long elevator shafts to the bottum and put my storage units down their like additional unmanned medibays. If there is a fire or a radroach problem, i just ignore them as tthe zig-zag rooms dont seem to spread the incident. If you put perm-pregger high intel dwellers in them, the will also produce stims but if there is a fire or rad-roach attack, they will automatically flee and return when the incident is over.

Just an idea. Sorry if its been covered before but I hadnt noticed it.