The spots with the highest concentration of VN traffic are often the ones that are the lowest priced. We give you the country information so you can make an informed choice.
If you are specifically looking for US traffic, do an "Advanced Search" by Tier1 concentration. That will give you sites with not only US traffic but also Canada, UK.
You're not really missing anything, I've had people try to sell Vietnamese traffic at 1c per click, and higher. I don't think it does make sense to ramp up their clicks since obviously, VN would still show up as the primary source of traffic and that deters many buyers.
I run an open marketplace, they're welcome to do what they want, set their own prices... but I wouldn't buy it personally

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