Dear Hunts Poorly,
The Robber Fly is really noticeable because he is big and zips around a lot and is very scary looking. Supposedly a fierce predator, but I have yet to see one devour something.
But his "noticiblitity" brings me to a theory I am working on about our focus, what we notice, and natural cycles.
You have to step back before the natural cycles were so disrupted to play this game...but, what if, things come to your notice not because they are particularly more prevalent this particular year, but they are messengers for certain people turned into particular channels..kind a like tv shows...there are different ones that appeal to different personalities. Too busy to go into it, but, why are there some insects that are symbolic and moving and cause people to form myths around them (like dragonflies) and some that are just there (like wasps, although I have an intense fondness for red wasps....)
Anyway, the robber fly is associated with the myth of Kokopeli, you can read more about them at this site, Robber Flys of Kentucky
which also lists a common name of one species as "hanging thieves" (isn't that a great kentucky-type name?"