These are galoshes - of sorts. I use them for wearing inside on the outside of my rain boots. But you could just as easily use them for outside wear if water is less of a daily concern for you. You see, I live in a rain forest. We get around 10 feet of rain a year. So wearing rubber boots is an almost daily occurrence. And taking off your shoes at the door is necessary. Everyone does it here.
But if you're working outside and need to dash inside for a tool, a drink, to go to the bathroom... well, these are great to slip on when you walk in the door! Or, if you just need to dash out on a rainy day to take out the trash or get something from the car these are the ticket too!