Thing is, my buttons leads to I/O expenders, and then all the I/O expanders to the MCU. They first IOE I looked at didn't have schmitt triggers on all inputs.

And honestly, I really preferred to limit extra processing on the MCU and concentrate on USB, and servicing the IOEs. I didn't feel like adding logic for debouncing if at all possible.

The 74HC14 may cost a few pennies, but it should help clean up the signals to the IOEs.