Assuming you throw out dead batteries, what's the harm in shorting them? (If we're talking normal nonrechargable alkaline batteries. If throwing away a lithium battery I'll definitely verify that the cells are totally dead or protect the terminals.)
Several fires at rubbish processing centers in my area were suspected to have been caused like that, and now, while it's not (yet) against the law here to dispose of them in this way, nobody will actually knowingly let you do it - it's strongly frowned upon.