But scorpions are even worse than wasps. They don't have the sound of their wings beating or the actual capability of flight, but they are much more alien looking -- and acting.
The thing with wasps for me was that both times I was stung, I sort of walked near a nest but wasn't really doing anything to disturb them. Or one time I was having dessert at a restaurant and a bunch of yellowjackets flew through the open window and ganged up on me and wanted my dessert and my coke (in this case they weren't aggressive but attracted to the sweet smells/tastes, I know, but still scary). However, every time I've seen scorpions, they were doing their thing, away from me, and I got the idea that unless I actually stepped on them, they'd leave me alone.
It doesn't help that I've been stung by wasps more than once, but never by spiders.