If you think about it, normally you have a vote to evict, so you only have to phone one number.
With a vote to save, in order to make sure someone goes you now have to phone two numbers, the ones of those you do not want to go at this time.
Does anyone else see this as a cynical money grabbing scam by Endemol?
You could still have a double eviction with a standard eviction vote, but that would not bring in as much lucre as what they are doing now.