Was rereading Dungeon Meshi the other day, and a thought but how controversial do you think eating sapient creatures on Golarion is? Most of the 'normal' races tend to have cannibalism taboos in their mainstream societies, but that only applies to each other and isn't a sure thing either. And plenty of monsters have basic / complex societies of their own and are sapient but eat the flesh of other sapient creatures, such as giants. Not to mention 'wild' monsters that are maneaters but are also still sapient, like dragons.
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Sapients eat sapients all the time on Golarion. Like you said, you can't really throw a rock without hitting another creature with 3+ Int (who will then start swearing at you for hitting them with a rock). If you restrict your diet to only nonsapients, you'll... well, you'll probably be fine, because there's still lots of common wildlife, but you're really missing out.
Eating dragons is basically a rite of passage in many cultures, and many Magical Beasts and Aberrations have entire paragraphs in their lore describing how people cook and eat them regardless of their intelligence... but there's no talk of humans eating giants regardless of how often giants eat humans, nor do you really see lore blocks talking about how people snatch humanoid fey out of the air and shovel them in their mouths. In general, I think it boils down to "the more human a creature looks, the more uncomfortable it becomes thinking about eating them."
It's probably controversial in most human societies to eat more humanoid creatures, if only because of the discomfort it can cause, but in my personal opinion even commonfolk would probably not turn up their nose at the idea of eating something inhuman that was still capable of speech, because while such a phenomenon exists only in ethical thought experiments on Earth, on Golarion intelligent wildlife has lived alongside humanity since humanity's dawn, so the culture around it is likely wildly different. Who cares if they can talk, those are just animals! And they're real good fried!
Note: cannibalism is taboo amongst humanoids for reasons beyond mere spiritual/religious concerns, because the act of eating raw humanoid flesh can sometimes cause Ghoul Fever, which can quickly spiral into a whole host of problems.
