Here's why:
* Different Time Periods: "That '70s Show" is set in the 1970s, while "Fringe" takes place in the late 2000s. This means a car from the 1970s would be considered a classic car in "Fringe."
* No Specific Mention: The show "Fringe" never explicitly states that the Vista Cruiser is the same one from "That '70s Show," nor is there any mention of the car's history or its connection to the show.
* Prop Vehicles: Most TV shows use multiple versions of the same car as props. It's common for shows to purchase several of the same model car to film different scenes, making it highly probable that the Vista Cruiser in "Fringe" is a separate prop from the one used in "That '70s Show."
While it's possible that the "Fringe" Vista Cruiser could have been the same car, it's highly unlikely. It's more probable that it was a separate vehicle used for production.