Uber has admitted they use an algorithm that is user-specific to determine pricing:
https://www.forbes.com/sites/nicolem.../#7b7af9cf7365
"
which determines what price to deliver based on different variables like your location, time of day, traffic patterns and even your user history with Uber"
So who knows what goes into that algorithm, but it wouldn't surprise me if having a premium card associated with your account impacts the algorithm...