Why do so many people believe that animals like spiders,wasps, snakes, or anything else want to hurt them?

Spiders, wasps, and snakes CAN hurt people, even if they don't often.

Many people fail to understand that these animals are more scared of us than we are of them. Since there have obviously been reports and accounts of people being injured by these animals (probably the person's fault anyway,) people jump to the conclusion that all of these animals can and will hurt them. Oftentimes, people who are profoundly scared of these animals DO end up getting hurt by them, because they freak out and flail around, making them EVEN scarier than before.

Sorry if that was no help, which it probably was. I guess this is more of a psychology question.

Most likely because they watch movies like Arachnophobia, Andaconda, Kingdom of the Spiders, Snakes on a Plane, or Eight Legged Freaks like its a documentary, then listen to stories from strangers that say "I had a friend of a friend who was bitten by a brown spider and he died in 10 min!". Of course these people can't produce a name or a record of this person dying from a spider bite, but they believe it as fact anyway.

The problem is people will believe things without verifying a source and then repeat them as fact to someone else.

The same reason anyone fears any unknown

Ignorance is at the center of it

These days we are not as in touch with nature as out great great forefathers were and too often rely on old wives tales for our eco educations

Because they are anthropomorphic idiots.

Their fear is based on ignorance, and the mistaken notion that animals are capable of the same malice that people are.

Most people don't think that wasps just want to hurt them, they're just afraid. If you had a fear of something, you wouldn't want people questioning you.

Because they are not like us. I think it's the same complex, as, say, racial issues.

One word: ignorance.

Because they would if they had the opportunity.