I answered a question about this a little while back - for a second I thought it was the same one.
Do your cats go outside? If so, thats how they're getting roughed up. Winter weather (and humidity inside) won't help much.
I don't know if there's anything safe to use on cats that would really soak into the pads. If there are actual splits in the skin you could probably rub a little antibiotic ointment into the cuts after washing the paws - but other than that instance I don't know.
And if your kitties are 100% indoor only, the underlying problem could be related to their litter box - possibly litter.