Ranked Ladder Point Clarification

A - 

B - 

Ok bare with me , player A  is half a rank higher , is or at least should be a higher MMR as they are simply a better player , in this match player B got 5 kills to player A's 4 , both had 4 assists and Player B also did more damage , so why is it player A got so many more ladder points ? not just a few but nearly enough to cover the entry fee