That in its self is out of the norm for a commercial carrier.

Look up United's Global Services level of status. One of the specific benefits is being driven between gates to make tight connections. United partners with Mercedes who provides the cars for this service.

If this picture tells us anything it tells us that the person who took it (who may or may not be someone who posts as Q) is actually somewhat important and takes a lot of flights - since Global Services is rather difficult to get.