I hear you and see your point. But does it really matter? The topic is/should be the addition of VAT which clearly is happening. Whether those paper receipts match the onboard account or not. The sums in the onboard account match the VAT on the receipts. Isn't that what this should be about? VAT of 20% charged in France. (If the person hadn't had FAS there would also be the actual drinks charges.)
And also the question of the DSC. Another person on the same cruise has the same thing, but they apperently got a credit or something matching the extra payment.