Well the issue with printing more money (which is much better than stealing the money) is that it devalues the currency. Since the Federal Reserve's creation in 1913, the dollar has been devalued by 97% i believe (at the time of his writing it was 95%), which is like a hidden tax. Basically, it has stolen $0.95 from every $1 without stealing anything. So the poor that the extra printed money is supposed to help actually hurts them because their money is worth less and less. Think of post-WWI Germany, where there was hyperinflation as they tried to pay off debts, and the people had to use the money to burn it for warmth because it was worth so little. And this does not hurt the rich as much (it hurts them a little) because 1) they are mega rich 2) they are often the ones receiving the new money 3) they make more money through the artificial monopolies by the government.
And the issue with injecting the money into the economy (which I would agree would be good if it wasnt the Federal Reserve doing it or stolen money from tax payers). If it was from the tax payers, it is just less money they are spending and more money the government spends, meaning resources cannot be allocated properly (similar, but exactly, to the Broken Window Fallacy). What the Fed does is buys assets with printed money, and through a system of fractional reserve banking, actually increases the money supply without printing money. Basically $1000 of money is turned into x amount (the ratio is usually 1:6), so it becomes $6000. Or whatever amount the Fed needs.