Usually that happens when there is salt on the ground. In fact, it happens a lot around here--I have to stop and brush off Rafi's feet.
However, when I lived in Wisconsin I do remember the cold bothering my old gsd Massie. I assumed she probably had a little arthritis in her feet.
Booties are a good solution but do be aware that if you walk a lot or walk in ta lot of snow, condensation will build up inside the boots and cause blisters.
Ruth & the 4 Legged Rescue Gang
Rafi the malaroo
Gio & Varda, the krazy kittens
....In my heart: