It really is cultural. Eating raw seal meat and the contents of the stomach was not considered disgusting by people who grew up with it.

I would guess much of it depends on the diet of the prey animal. Eating the contents of a carnivore's stomach would probably be awful, but that of an obligate herbivore is probably not as bad, comparatively, since it would mostly just be plant matter, perhaps slightly fermented.

You only need to take a look at the difference between the feces of carnivore and herbivores. Cow dung or rabbit pellets really aren't all that bad. Wolf or otter feces, as two examples, is pretty vile stuff.

More a technique in preparing it. Just like anything else that may seem unappetizing on its own. Sweetbreads are pretty tasty, and tripe isn't the worst if it's prepared well. Intestine can get tough if not prepared properly, which is not pleasant to me (though my in-laws seem to like it that way).

I think a lot of eating organ meat involves washing it or soaking it to get the more unpalatable flavors off.

Not something I've really been adventurous enough to try though.

It's all about preparation. I don't think I could eat certain organs without puking just from the thought/looks. You couldn't get me to eat heart for example. I've tried to but couldn't get over it (chicken hearts actually). And even liver, I'm not sure I'd eat.

German Liver Sausage? That is one of the most delicious things on earth!

How's this for a "recipe": Beef trim (50%), beef liver (20%), beef heart (15%), and beef kidney (15%).

Take a nice piece of rye bread (best is a real sourdough rye bread), spread the Leberwurst very thick, top off with a cornichon and/or pickled mini onion. Heavenly.

I've tried chicken hearts on a skewer at Japanese restaurants a few times, and of all the organs I think it's the least organ-y. It's a working muscle and pretty much tastes like it.