Mob weapons

I've been hunting cyborgs for a while and it struck me that they use a wide variety of weapons. From sleekblasters to rifles to novaflows. Today I fought a borg who slapped me with a cake ffs!
Their damage type also varies with the weapons they use.
Is there any good reason why all human mobs use identical weapons? It would add so much if soldiers would use something besides solar-powerd rifles. Maybe an MA with a claw, fighting unarmed, or even dual wielding. Enforcers with swords and beams.

I'm not saying mobs should be harder or softer depending on their weapon, just the visual element would make the game so much more diverse. The cyborgs do it so why not all mobs???