This is quite the surprise.
Updated May 1, 2019: Dana Cowley, Senior Marketing Manager at Epic Games, clarified that the company has “not announced plans to stop selling the game” on Steam, as previously speculated by The Verge. Cowley continued, “Rocket League remains available for new purchasers on Steam, we’ll continue to support it on Steam for existing players after it comes to the store.” The original story follows.
A few days ago, Epic Games’ Tim Sweeney said that if Valve stops taking a larger cut of revenue on Steam, it’ll stop making exclusive deals. However, it seems like the company has found another way to acquire exclusives. Instead of simply paying for the partnership, Epic Games is buying studios and making their games exclusive to the Epic Games Store.