Banks make somewhere around 450 billion in revenue each year. https://www.statista.com/forecasts/409713/banking-revenue-in... This program made them 1/3 of 1 month's normal revenue
That also means that they could have easily waived the fees without taking much of a hit, just out of solidarity.
They've lost far more even with the fees they collected from this program.
As someone said above - doctors are not working for free, why should bank employees?