Does it matter if that company is from EU? Even a new engine centralized in the US won't be able to operate in the EU without substantial cost. That's a pretty big market/data source to miss out on.
Even if you pay Google €0.01 per click, you still can get an impression under certain conditions.
If the European ad-buyers are funnelled into a subset of ad auctions, the average prices in those auctions should be higher.