It is clear they are designed to keep the feet warm when venturing through the cold climates of the alps. As shown in the image, there is an inner sole to the show, designed to hold in place the instillation material. The outer of the shoe had leather placed across the sole to prevent slipping on surfaces.
Such designs tell scientists today that the people of the alps were quite crafty in their clothing designs. The practicality of these designs are unquestionable as they are cleverly designed to keep the feet warm throughout the freezing conditions and in a way that would minimise chances of slipping.