Yes but you’re not paying for the area the blade covers - you’re paying for the blade. Simplifying (to an extreme) for the sake of illustration - a 20m blade costs twice as much as a 10m one but produces 4 times the energy.

Obviously, cost scales more than linearly with blade length but it’s a bit like big O - the n^2 factor dominates. This is why wind turbines have been getting bigger and bigger. And why the cost of domestic or small-scale wind turbines remains stubbornly high despite the dramatic fall in the average cost per MW seen for wind turbines - as the falls are largely driven by the ability to manufacture larger and larger turbine blades. While falls in costs for solar PV can be seen at every scale.