Yes, but don't overestimate this density. It wasn't as it is today. But I agree that pillaging actual CITIES should reap enormous revenues. But I can't say that I agree with the idea that pillaging the "relatively" empty stretches of land between the cities should reap the same degree of revenue as a city.
This is why I would like to see special tiles with such resources to be pillaged. Oases in deserts to be foraged, to small populated tiles to be pillaged etc.
Don't know if this is doable yet though.
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