Why does that matter? If you don't like your current job, start looking around until you have a new offer in hand. That new offer in hand is now your leverage ("bargaining power") if you really like your current company. Otherwise if they "call your bluff" you still have a job.
Lame living by someone else's ultimatum also. If you had a union you'd have to go on strike for shit you don't necessarily care about and you would have to wait for somebody to age out to get off of pager duty. It's outsourcing responsibility of your life to someone else.