they cant sit with the money under the mattress, its got to be on the street earning. Now a 5.5% savings account gets the cash to a bank that vigs it out at 10-29% and the economy rolls. Buying stocks is an alternative that will outstrip the banks but if it was taxed as straight income both the savings account and the stocks will still make money. As far as taking the cash out of circulation, the first thing a rich person learns is never touch principal, sitting on assets will dig into the primary pile.
thanx,
bill