You are asking about different series and two different cars all of which different teams/drivers. I don' know if that is a fair comparison. What you really want to talk about is whether the tire rule benefits anyone other then the organization that mandates it and the purple tire company.
I found this on the net don't know if this applies or not. "The Sherman Act also makes it a crime to monopolize any part of interstate commerce. An unlawful monopoly exists when only one firm controls the market for a product or service, and it has obtained that market power, not because its product or service is superior to others, but by suppressing competition with anticompetitive conduct."
If the purple tire money goes in to the purse does that help the idea of spending your money on the purple tire. Kinda like Lawrenceburg mandating Budweiser products at the track, just tears me up drinking an inferior product.