Many of the reasons robot swarms would be helpful to us are also tools that could be used for evil. Small autonomous robots are invaluable in being able to enter unstable or radioactive buildings to gather information, find trapped people, or bring back samples. On the other hand, the same idea could be used for a nefarious purposes to map out the defenses and terrain of the next place to be invaded. There is an episode of The X-Files about robotic cockroaches of alien origin looking for sources of methane they can harvest should their creators choose to visit.
The Cybermen from Doctor Who run a similar gambit in ”Closing Time” when they release silver rat-like Cybermats to scout out power sources and siphon electricity to the ship they’re trying to repair.
By mapping out the efficiency of the communication among superorganisms, engineers can design better traffic patterns to avoid traffic jams and collisions. It’s also an idea that will get us one step closer to self-driving cars, which I personally look forward to.
After all this you might start feeling a little concerned about your safety and privacy in an increasingly robot-filled world. Drones fly through the air spying on you, there are robotic flies on the wall watching your every move, and soon even your car may turn on you! Don't worry though, I'm sure the water is still safe. ...Right?