Using rotary encoders with no interrupt pins
If you really poll much faster than the encoder moves then this will work.  Whether it is a good idea depends on how fast the encoder can actually move and on how important it is that you don't miss clicks.  I certainly hate it when I spin a dial to scroll through a long UI list and it moves slowly backwards, although there is no real harm done.  If the encoder is feedback from a motor, missing clicks could cause bigger problems, like mechanical damage.

You could use dedicated logic to make a counter, or you could use a different microcontroller that has a built-in encoder peripheral, but for most purposes polling is probably fine if you do it fast enough.