Why would catholics (and other christians) pretend they know for a fact hell is real, without any evidence?

So as a Catholic, i present hell as something i believe in because of my faith rather than as a definite place. i try not to force my beliefs upon people. but i feel like some of the people are not pretending they think it is real, they just speak as though it is real because they truly in their hearts believe it is a true place. faith is knowing without evidence, therefore many people believe it and dont realize it may be offending others