In an unsurprising turn of events, they directly went with what they said before launch and will add a way to purchase Wumpa Coins when the next Grand Prix starts.
Even if it was obvious with Activision behind, it's still very disappointing considering how many already thought the game was grindy. They obviously had to monetize the game somehow, but they should've been transparent with this.
SourceAs always, the Pit Stop will be stocked with new and returning characters and cosmetic items, which players can unlock using Wumpa Coins*. With all this content available, there will also now be a way for players to fast-track their Wumpa Coin collection if they like. Starting in early August, players will have the option to purchase Wumpa Coin bundles from their game console stores to supplement the Coins they earn by playing. This option won't change the game's core mechanics – players will still earn Wumpa Coins by playing the game in any mode, just as before. They will just able to purchase additional coins if they choose.
Even if it was obvious with Activision behind, it's still very disappointing considering how many already thought the game was grindy. They obviously had to monetize the game somehow, but they should've been transparent with this.