But you're assuming here that "the rich" investing money is creating more growth (and you stated earlier, helping poor people more) than the government would.

I think that's a difficult statement to back up in the best of times, although it's certainly a difficult thing to prove either way (moving this question beyond the level of anecdotes is really hard). However, when we've got a persistent demand shortage like we have right now, it's much less of a tricky question because of the multiplier effects of consumer spending.