Ironically, this kind of hate requires no effort, someone says “GROUP BAD!” and you just sneer and shout towards them. It’s way, way easier to blame a group than understanding all the things that are making your life/city/country/world go wrong
“Of COURSE the evil jew gay black communist feminist conspiracy is the root of all evil, they hate MY way of life!”
There’s also the point that most conspiracy theories capitalize on the “this is a secret THEY don’t want you to know!”, so it makes people feel smart (despite them believing in utter bullshit)