Because humans love Awe.
We love finding new things. Be that new inventions, new lands, new worlds, or new flavors of old ones. By examining the weird stuff, we discover the new stuff. People, while examing the "weird" ideas, sometimes find some small spark of truth in the "weird" thought or idea. This spark of truth nags at them to look closer at an accepted idea and in so doing, sometimes, they find a previously undiscovered flaw in the accepted non-weird thing. The new thing is "weird" only because it takes us (humanity) a little while to process the new "flavor" of the changed idea, or new technology or new thought process. Sometimes what we discover is that the weird idea is just that, weird, and flawed. But people will sometimes cling to the obviously flawed "weird/non-weird" idea because it inspires awe in them, or because it comforts them in some way.
Belief in magic, miracles, fairies and fairy tales... of things greater than ourselves... of new things, new technologies, and new ideas, inspire us with the awe of "what if" and is how we grow.
Without the dreamer dreaming up some "weird" thing, we would never find anything new. We would never discover truth as opposed to popularly accepted beliefs.
...history has taught us that what seems weird/improbable/unpopular today might just become proven/true/accepted and non-weird tomorrow.
The world is not flat.
The Earth is not the center of the universe.
Humans can fly.
Jesus is the son of God.
Invisible pink unicorns exist.
Bigfoot knows where they are.