Bats in your house are a problem because of droppings. It's like any other wild animal nesting in your house; they can damage the property and cause general filth issues. My uncle dealt with it by sealing the attic with insulating foam after getting all the bats out and cleaning up the mess. The ones in the barn he didn't worry too much about.
If you have a hornets nest in your house and it doesn't bother you, well, you'd be the first person I've heard of who tolerates that!
If you have a hornets nest in your house and it doesn't bother you, well, you'd be the first person I've heard of who tolerates that!