Both Islam and Judaism are based in the Middle East (unlike Christianity which left the region around 300AD) where resources aren't abundant. If one takes out the religious aspects, one can take two roads to why pork led to being banned. One is that it's a animal that takes limited resources and gives nothing between it's birth and and it's death. Secondly, when it was slaughtered and not cooked well enough people became sick from eating it's meat. For religious purposes, it would have taken too long to explain why during the time period the books were created. Thus they simplified the rules to state that animals must have split hooves and chew it's cud.