But then you're having to ignore an even "greener" option. That's using and promoting ad blocking in general to lessen the environmental impact of consumerism. The thing with Ecosia is that it seems to ignore the damaging impact consumerism has on the environment. Instead, it encourages it by urging you to expose yourself and your friends to advertising.
But then that's up to you, right? Ecosia does not encourage you to buy anything, but if you search for products, it suggests places where you could buy it. I don't get your point.