Although slightly askew of the main topic, an interesting comparison could be to look at skydiving incidents compared with motor sports incidents (I have no statistics nor any idea where to find them). The point is skydiving is a dangerous sport, whereas for the large part driving to the drop zone is a mundane activity. People are more likely to be pushing the limits of their capability whilst skydiving - there can't be too many who attempt to do so in driving there, and so the number of fatalities is inherently going to be larger. But where motor vehicles are pushed to the limit (in motor sports), the risk will increase.
However, the very nature of most people who are willing to skydive can create the illusion of more safety. Most will be very anal about safety (no bad thing) and likely to want to feel complete control of a situation. This coupled with the adrenilin of the skydive can lead to a feeling of being able to deal with any situations.
When driving to the DZ, this level of control of a situation can be removed and placed into the hands of others, without the same perspective on safety, and so can create an uncomfortable feeling of danger.
So whilst driving may be a lot safer, it can feel otherwise.
fell free to shoot down any points made here - I am very very new to skydiving (damn that British weather)