Not eating pork/pig for religious reasons is common sence.
Most religions, muslim, jewish and early christianity were 'developed' in hot climets. Pork/pig meat can go off very quickly and is one of the few meats that can poison people if not kept cool.
In later days when christianity became the chosen religion in europe/UK we pagens already ate pork. Due to our milder climet it was safer to eat.