I don't think it's a one-way flow. Here's a company that makes, say, cars. And here's a company that invests. Money flows into the investment company and away from the car company. At some point, the rate of return on the car company starts looking good enough that even the investors notice. At that point, at least some money comes back.

Now, you may say that net "well-being" of society will go up if we make more cars and fewer investments in financial firms. (In the end, you can't eat money.) But where the line should be drawn is going to depend very sensitively on your definition of "well-being". That's not an easy question to answer, even before politics gets involved.