So even though the death penalty is mandatory for these crimes it is done anyway - further proof, if any was needed, that increasing the punishment does not decrease the occurance of the crimes. The eastern part of Malaysia has a strong element who believe in the implementation of Sharia law, so it is unsurprising that the punishments are so strict - even though, in my view, neither the Hadith nor the Qu'ran demand the prohibition or even abstention from drug use.
Malaysian gangsters can be very tought. Such things as throwing grenades into police stations and shooting with rifles at police happens there. I guess their logic is simple: Kill before the law kills you.
I don't know the figures, but I think the drug-dependence among Malaysians are more than double than among Europeans.