Kinda annoying when there is a red light at a busy traffic intersection at the bottom of a steep long hill.

Half of the time, I am usually hauling weight of something significant (groceries, my own clothing) while cycling.
I use toe clips and have for 2 decades. I could not imagine levering myself with double pannier weight up on bike from a dead stop to grinding steadily up a steep hill without keep my bike-shoe-shod feet connected and stable on the pedals.

And I don't stand up while spinning up hills. It's just my style of cycling up hills.