I'm not convinced there is a trade-off between economic efficiency and inequality. If people who have a lot of money hoard it, resources getting concentrated could cause the economy to shut down. I used to be puzzled that victims of 419 scams could believe that 10 million dollars would fall from the sky, but what if these are people who already had 10 million dollars fall from the sky? It could be higher taxation could get money away from people who aren't in a position to put it to work for themselves or society.