GirthyBurritos spotted this vehicle filling up at an interstate exit. This cat is clearly headed for a new life in a new place. Since he had to strap his cat tree on top, you can assume that the interior is full of catnip, Fancy Feast, and hair ties. The reddit thread underneath gives a collaborative speculation as to his story.
"Sitting in James' truck at the gas station, I began to question my choice to leave. No. Karen and James had their chance, that sparrow was the last straw.
I had hunted, killed and gifted 47 prey by that point and every one had been met with disgust and rejection. After duly showing gratitude for my humans handing me ownership of themselves and their land, Karen grabbed me by the neck and rubbed my face in the delicious meal I had brought them. I was baffled and deeply offended. I didn't understand them, they didn't understand me, it was time to move on.
Without me patrolling the garden, Karen and James would most likely be eaten by dogs. So be it, I had no more use for them."
...so, with 2 kilos of catnip and my lookout post strapped to the roof, I topped off the tank and left town.
"We were just outside of barstow when the catnip began to take hold"
I would watch this movie.
Further down in the comment thread, the plot gets much weirder. Wherever he's going, he's definitely in the driver's seat. I bet his name is Toonces. The moral of the story: Never leave your car keys out where the cat can get them.