Greetings
Between the fuel meter and your aircraft fuel tank there is a manifold, which contains the 100 kg missing

, because when they stop refuelling the fuel has already been trought the meter, but will remain is the fuel tanker manifold as he is disconnecting the bowser from your aircraft

Some airline have agreement with tankers to provide the manifold capacity (100 kg, 50 kg..) and to substract that quantity from the meter
kijangnim,
Surely the 100kg which has been left in the manifold downstream of the meter (ie after the meter) will sit there for the next aircraft thus the first 100kg are delivered un-metered and the last 100kg not delivered is metered = No descrepency!!????
The only exception I can think of is if the last 100kg left in the manifold is somehow removed from the manifold before every delivery!
Which Airlines deduct this 100kg figure from their uplift?