I came from a “natural” culture as well. The old South. And we had a nickname for our “accidental” litters - posthole puppies (meaning that you threw the unwanted puppies down into the nearest postholes of the fence you were perpetually building). They also lose a large number of the litters to parvo and other diseases - the only reason many cultures are NOT overrun by feral dogs is natural attrition.
I got out of this culture deliberately and rather forcefully through education - I lived right down in the middle of it - hog guts and chittlins and all. It was really rather dreadful. My family still lives in a way that involves heartworms and dogfights and hogs in the backyard, which, truthfully, is the other side of that “natural” culture that you are espousing. You are fortunate to be able to pick and choose what you like about it - not everyone has that choice, and it’s rather elitist to do so, truthfully. Which is fine, as long as you acknowledge that this is true (ie. that you are picking and choosing from that lifestyle). I was fortunate enough to claw my way out of that life; learn that things could be different. But I don’t forget that it’s complex in that culture - there are many admirable things about handling dogs in there, as well - I did learn a lot about training dogs AND horses through this experience.
I think it’s romanticizing pastoral cultures to not acknowledge the other side of that argument. I’ve traveled extensively in Central America (El Salvador, Nicaragua, etc.) and was frankly traumatized by the condition of the animals there. It reminded me way too much of the rural South of my youth. We are lucky to be having this argument and to be able to pick and choose the behaviors we emulate from them :D.
So I suppose my point is; you are lucky to be able to make a decision to spay/castrate your animals - like so many things in life, it’s not always an academic decision in these cases, but comes down to long-held cultural beliefs, financial difficulties, etc. 