Well, I wouldn't have phrased it quite so....colourfully, but yes, the restriction on eating pork is related more to hygeine than religion. If you read the Iliad by Homer, there's a lot of repetition about how offerings are made to Gods etc, in it's own way it's an instruction manual for the masses on how religion was supposed to be practised at the time, cleverly wrapped up into a story. The Bible is very similar in a lot of ways, and just as Zeus smote people who offended him and rewarded those who pleased him, a similar 'stick and carrot' method is used in the Bible.
I wouldn't say that it's an instruction book on how to kill people but, once again, just as the Iliad used common prejudice to get a message across to the public (witches chopping up babies etc.) the Bible also was a reflection of public opinion. Releasing a book called 'Worship God, he likes man-sex' would not have been a good political move at the time, people like to hear their own prejudices confirmed from a higher source. The Bible, in reality is no more in favour of wholesale slaughter than just about every book around at the time.