1) They are warm. Thick soles mean distance between my toes and the cold earth. My toes were complaining so much about being cold that I had to listen to them in the end. Otherwise, I fear, they would have gone on strike.
I was managing with other shoes until recently, then NO MORE! My feet finally said, "BOOTS! WE NEED BOOTS!" And so hence my metamorphosis from dainty, elegant female (?) into striding, hell-for-leather, female which is probably who I was meant to be anyway!
There once was a time when stockings and other stuff was the mode of undergarment and shoewear. But, as you can see, it is now very thick socks, very white longjohns, ....and BOOTS!