This is what a haggling culture actually looks like. There's an assumption in this thread that in all "non-Western" cultures, haggling is the norm. But I think it's important for the seller to imply consent first.
Haggling is the asking for consent part. Are you suggesting that "can I haggle with you?" is somehow more polite than "would you sell it for $x"?
I think it's honestly kind of infantilizing to assume someone who is selling goods for a living is going to be somehow tricked or manipulated into selling at a price they do not want to sell at.
It's not about manipulation, but manners. Where I live, you literally do ask, "Is this the final price?" Or a lengthier way might be, "This is a beautiful thing and I would love to have it! But alas, it is beyond my budget."
Most cultures are not as direct as American. In the US, it's a virtue to save time instead of dancing around the question. But in some cultures, dancing around the question is a mark of respect. You first acknowledge that the seller has been generous and then ask them for further generosity.
For the seller to imply consent? There's another article on here about "No" being a complete sentence. The seller is not forced to haggle at all, they just have to repeat the same price.
I think it's honestly kind of infantilizing to assume someone who is selling goods for a living is going to be somehow tricked or manipulated into selling at a price they do not want to sell at.