yesterday, I buy fish (monkfish 22 90 / kg). The...

yesterday, I buy fish (monkfish 22 90 / kg). The fish is weighed: 2kg650. I ask that it be prepared, that is, the skin removed.
I collect the package and when I get home I weigh the package again and, oh surprise! 1kg 750 !!!!
How to imagine that there was almost 1kg of skin ????
Now be very careful! In the fish department, honesty does not seem to be required !!! Quite ashamed, Monsieur Leclerc, slayer of the cheaper life.