There's a long evolving history behind the subject. For one I used to own both a Japanese Chin and a Pomeranian. He trolls me incessantly about the Chin and my burning want to have one again... But the "dog in car" joke has a long history with us.
It's getting hard to remember but I think it started innocently enough. With us dueling each other to identify any dog we saw while out in the wild. We use to watch dog shows on the weekends, for the hell of it.
That morphed into taking phone camera photos of dogs in parked cars. Especially if they were seated at the wheel. We toyed with the idea of making a calendar out of our photo collection.
Witch I believe brings us to today. Where the joke is now a movie scrip of dogs racing cars. Completely straight faced, no horribly over animated CG dogs, and No mash potato eating CG mouths. No dialogue at all in face. Told in utter seriousness.
What this decade long joke will mutate into next is impossible to guess.