It's simply easier to tell people not to eat certain foods with a religious "because God says so" if you cannot really explain it to them sensibly, lacking the scientific means to explain bacteria and parasites.
How about "It'll most likely make you sick." It's not sensible at all to say "magic", and never was - it's an easy, unthinking cop out, and that's the only description that's valid. I'm not trying to argue with you here, I just want you to think outside what the religious nuts are pushing down your throat.
"Morals" are nothing but a convention dictated by society.
I agree with this to a point - if you hadn't grown up in a society, I think you would still have morals. I think there are certain morals it's likely that everyone in the world has - this implies to me either 1) there is a higher order of morality or 2) we all have the same morals, and immorality is a convention dictated by society.
It would (hopefully) still contain the parts about not killing, stealing and lying.
To be fair, I doubt very much those are the parts that made these religions successful. The horrible "kill others" message that is prevalent throughout these "holy" texts is what has allowed religions to fester and build up like a boil on society's ass - those that preached peace and tolerance would very quickly fall away to religions that preached intolerance with physical violence.
So, biologically, I should go over to my neighbor that I hardly speak to, bash his head in and take what was his
What?? No! That's not biological at all! We are as social as we are familial - it's likely someone who is perhaps not a friend today may become one tomorrow and aid in social/economic/biological needs in the future. This is best practise. i.e. maybe your neighbour will become your brother in law some day?
its morals are usually rooted in a religious background
I dislike this argument. Where is there proof that this is true? Who says the morals written in "holy texts" didn't exist before the "holy" texts? Just because it's an old document in which ignorant peasants attempted to codify some morality doesn't mean that the morals weren't there beforehand.
I just want you to consider that religions haven't really given us anything beyond what we may already have had except for perhaps being a foil for certain art, literature, or perhaps, philosophy, and even then, it's questionable that we wouldn't have had those without religion anyway.
