My prefix has a value when defined,
My infix has value when it's refined.
My suffix is not usually moved,
My whole is after something's been removed.
What am I?
Hint 1:
If you steal my infix, you may end up at my suffix.
Hint 2:
Same answer but not necessarily the same prefix/suffix/infix:
My prefix does not play but is part of the game,
My suffix is a place for passengers of a train.
My infix is shouted as warning of danger overhead,
My whole can make a specific type of bed.