What you describe has been discussed. I've read documentation about it.
Humans are the only know species of mammal/animal that deliberately eats a food which they know will cause pain.
Obviously before freezers and fridge, spices were used primarily to cover spoiled meat and spoiled food.
However, some authors have postulated that in meager food stores, the pepper would give a filling feeling after eating.
That is to say, even if you eat only a cup of very spicy food, your body and your brain knows you just ate something.
And theoretically that is comforting to your being.
Yea but, back to your point, wild animals will not touch it.
There is something to that... My last Near Missus said something like that, and practiced it...
She said the secret to eating less was in feeling satisfied by what you DO eat... Hence, taking the time to fix really good food, and jacking up the taste value(s) had a tendency to make it stick in your head as satiation.
That ain't all of it of course, as she also balanced protein with sweets and fats and other such things.
But I found she had a proper point. A peppery or mustardy tang tends to resonate and reside longer on the tongue, giving the illusion at least that you've recently eaten say a half an hour longer.
And there is something in the food quality thing too - If you stop off at Mickey D's for a quick instant satisfaction gut bomb, you'll find you are up looking for a snack in an hour or two...
But relatively the same amount of a nice spaghetti that you've taken great care in preparing, and smelled cooking half the day, till you are nearly nuts to het it on your plate.... The satisfaction of that meal will last all night...
Alright so there is that slice of apple pie in the fridge that you remember around 11pm... but you get my meaning. You don't NEED the pie... Well yeah, maybe you DO NEED the pie... but you REALLY don't need the pie. And THAT's the difference. Sorta.