I think its pretty self-explanatory, so I'm not sure why you were saying "what?".
If it was to the Ogres/Goblins then yes there should be a little more lore to them and their tribes.
If it was to the bandits/marauders then maybe your remark was justified. I'd say give them some lore if their names wern't so vague. I think there mainly just gameplay factors, hence their name. They're basically creatures with a good inventory selection after you kill them.
I was serious about the others, too.
We only have assumptions. I know they're just generic enemies there for their loot tables, but they have some lore if you examine their CS statistics.
The Bandits and Marauders hate each other and are classified as unfriendly, for instance. Likewise, the Vampire faction is slightly friendly to Undead and Beasts, but of course that goes with usual Vampire lore from classic DnD and mythology. Other slight things too, like Highwaymen technically being considered Bandits, Conjurers being friendly to Daedra, but unfriendly to Necromancers and Undead etc. There's probably a lore reason for all of this for the game mechanic to actually exist, but an obscure one.