So ... finance definitely has a rent-seeking component, having reviewed some of the literature.

But it also has the effect of starving other fields of talent and technical expertise, of bidding up their costs, and related effects which are more similar to Dutch Disease / Resource Curse. The number of physics, maths, and engineering grads working at banks / financial institutions rather than at science / product R&D firms, for example, is pretty staggering.

Still mulling, but thanks for the food for thought.