In the UK, at least, the Bank of England used QE money to buy government bonds. This meant that the bond-holders could exchange their illiquid bonds for cash,

In the UK, at least, the Bank of England used QE money to buy government bonds. This meant that the bond-holders could exchange their illiquid bonds for cash, which they then needed to do something with. The BoE then collected and destroyed government payments on the bonds, so the net amount of money doesn't change in the long-term. One side-effect of this is that the cost of bonds went up -- demand had increased -- so the profitability of buying them went down, meaning the banks were naturally incentivised to do something else with that money. It's not a panacea, but it is quite a neat lever to have when you want to increase the supply of money without actually spending any. Unfortunately it still looks like the banks are being given lots of free cash, but it's not actually free.