Why is it okay to eat pigs, but not dogs.?

The best answer I can give you out of the top of my head is a pig is a domesticated FARM animal, whereas dogs are pets. There are many people out there who wouldn't eat a pig either, and sadly many who think eating dogs is perfectly acceptable. However, in most civilised societies, this habit isn't. And I would add that we slaughter farm animals humanely (usually!) whereas dogs for eating are killed in the most horrific ways imaginable.