Personal jets consume a significant amount of resources that are limited on the earth as well as pollutes at a serious rate per person. If private transit is for reasons of safety, the person(s) using the private transit should at least consider a sort of "carpooling" when traveling by private jet.
As far as policies, fees should be applied to those traveling by quantity of person per resource expense. An example being that for 5 people on a single jet should pay significantly more fees than someone that is taking a commercial airline. All fees would then be recycled into either going to energy conservation and research in order to develop methods of safe but low-resource transit.
As an organization that promotes the world working together, I feel it is probably a target for individuals and parties wanting to send a message to the world. It would be an easy way to harm several countries at once. Therefore, I feel all jets, private and otherwise, should go through strict security checks upon arrival.
With so much money sitting in one isolated location, there should be some accountability on the side of the World Economic Forum to ensure flow of participants into the event. The increased amount of traffic is an accident waiting to happen, and unfortunately it will be the simple person which is impacted by such a tragedy.
Money is everything, you drive down the street and will not see something that is not attached to money in some way. Having lots of money means you can do what you want; whether you think its fair or not its reality. Get over it. Life is not fair, then you die.
There's no reason for the World Economic Forum to go to such lengths. For one thing, if they have attendees arriving by private jet, those people have so much money they can afford not to care what the poor people think about their modes of transport. The rich are different than us, get over it.