The reason you can't give away a mattress is bedbugs. If you know what to look for, a bedbug-ridden mattress can easily be avoided. And you can also buy protective breathable covers that keep the bedbugs either in or out. But most people don't know what to look for, or don't want the liability of being wrong.
We gave away our mattress to a non profit. They sent some people out to inspect it ahead of time. They said needed it ASAP for someone who was moving away from an abusive relationship - it was supposedly going directly from our house to the place she was being put up.
