Your description makes one implication, which may be misunderstood. Regardless of how wildly unimaginable the behavior-changing disease effects may be, the causative factors/parasites don't really understand that they are altering the behavior of their host.
Viruses, for example, don't really have any intelligence, they are simply constantly changing, some of their forms seem to exhibit a specific response in a series of hosts, and that's how they come to be. We interpret the behavior-altering symptoms by ourselves, but that was not a "goal" of the pathological causative factors at all. The entire process is driven a lot more by chance (if not entirely), than by intelligence.
Speaking as such, the travelling behavior pathophysiology can be more "cynically" tracked down to some more classical system. Which leads us to:
The Vestibular System is your target. The system that informs the brain (among other things) about the current motion status of the body (linear accelerations, gravity, rotations in various planes, etc.). The vestibular nerve transmits information from the otolith organs to the brain. As you probably expect, the involved mechanisms are extraordinarily complex, but you can definitely "invent" a mechanism that is quite plausible. A trivial example:
The nerve transmits sensory information related to the motion state. Therefore, when relaxed, no information is transmitted. Your virus could, somehow, reverse this mechanism (there can be plausible ways for this), so that the nerve fires when you are not moving and fires a lot less when you are moving, i.e. motion inhibits the neural cells.
You can see where I'm going with this! If patients feel irregular motion patterns when they are standing still, and stillness when they are moving, then they may become dizzy when standing still and the only thing that can help them relieve the dizziness is motion. Therefore, patients will seek to be in motion as much as possible. Tune the effects down a bit, so that dizziness does not set in very quickly when someone stands still, and you will have a fair balance of people that feel strongly annoyed when not moving, and will have to move often to feel relieved. Slowly, it will not be uncommon for victims to try to spend many hours in moving vehicles, airplanes, etc.
So, travelling is not "intended", but helps to relieve the symptoms.
The only drawback with this "theory" is that a fair level of medicine can, at least, trace that down to the vestibular system, because travelers practically "know" why they are travelling. Maybe you can fine-tune the symptoms a bit more, so that it is not entirely clear to those affected about why, but they do feel a significant ease and wellness when in motion!