For some reason, I've always assumed the government being backed by Earth in "Gropos" was pre-spaceflight... Can't seem to find anything to back that up though.

It occurs to me that the B5 setting is a post-colonial one, with the end of Centauri rule over other species still within living memory. I'd assume that blatant attempts to occupy or exploit primitive worlds is frowned on, but sending in ‘advisors’ or establishing ‘protectorates’ over low-tech systems is pretty common.