Here are some typical answers(ranked in ascending order of corniness) I get from managers/bosses whenever I bring up the importance of having unit tests and code coverage as
My short and incomplete advice would be to:
Just change jobs. A company whose managers give that sort of answers is going to fail anyway, and soon. Get out before it's too late.
Reverse the blame game. Make an official statement every time something gets released without unit testing that it has been done so, and that you are not guaranteeing it's bug-free.
Write down the time you spend on tasks, separating bug fixing after failed deployments, and total it against a (potential) time allotment for writing unit tests.