Ben explained it very well: Lack of experience among drivers, very little budget, equipment or manpower.
For example, our county has several hundred bridges, all of them concrete, many of them 20+ feet high. And two sand trucks.
The most we'll ever see is a little sand spread on the major bridges when icing conditions occur, the rest of the time we're on our own, but it's only every 3-5 years we get weather that MIGHT keep people home for a day or two.
Also, more than snow, we have "black ice" here just like a lot of places in the central plains on down to the Gulf. Snow isn't really that much of a problem here, we never get more than a few inches at at time and even dumb drivers do ok on packed snow, it's the thin sheet ice that really causes problems. In the panhandle plains there may be a few snow plows, I don't know.
Really it's no different here during a cold snap than some of the northern states when an abnormal heat wave passes through. I remember hearing many times on the news of temperatures in the mid-80s wiping out hundreds of people in cities where few were equipped with air conditioning.