In the old days we took the zamzam water off the pax in Jeddah, empty them, then the bottles were refilled at KUL on arrival
You are not going to make friends in Malaysia !
I remember stories of the very first Hadj flights from Mauritania to Jeddah by Spantax, (early 70's) where on the inbound flights people were starting fires in the galley to brew tea and on the return leg they got a few 100ft max rate climb after level off due vast amount of zamzam water ad holy sand carried as in hand luggage . I thought that by now the lessons were learnt and that hand baggage is now weighted there . is it not the case ? .