I know: that headline is hate speech. But the fact is that it's sometimes true.
Take education. Here's the kind of reliable payoffs we get from investing there:
And this doesn't even count the long-term aid to business that education spending provides.
Remember: few businesses are seriously constrained by a lack of investment capital (only 9% in the U.S.). Many are seriously constrained by a lack of skilled workers (35%).
Do the math. No private-market investor can expect those kind of returns. If rich people all gave a larger chunk of their (nonproductively-invested) incomes to government to invest wisely, everyone--including them--would be much better off.
Oh, hey: that's called progressive taxation! And surprise surprise, it results in more growth and prosperity. Whodathunkit.