Spiders, yeah, woopie. Still, finding one crawling up your shirt can instill a certain type of fear: they can't really hurt you, but they can make you hurt yourself...
My daughter just said, "One time I saw a black spider on a railing up to the library. Right before the door there's a step. I got scared just seeing the spider, ran to the door, and tripped over the step. The spider didn't hurt me, but I sure hurt myself!"
(lessons learned, eh?)
It also makes one realize how insignificant, irrational, (and even harmful) some fears truly are.