Grand Theft Auto V is free on the the Epic Games Store today. For a limited time, people can add the game to their accounts with a zero-value purchase. This follows the addition of Red Dead Redemption 2 to Xbox Game Pass earlier this month, meaning that both of Rockstar's current-gen juggernauts are being given away as incentives to sign up for games platforms and services.
With more than 120 million copies sold to date, Grand Theft Auto V has been an incredibly enduring hit for Rockstar, in large measure thanks to the popularity of GTA Online which takes the action out of Rockstar's genre-pastiche single player campaign and into a much weirder, open-ended sandbox where alien gangs battle in the streets and GTA Online bourgeoisie flee to the suburbs.
So it's unlikely that Rockstar needed to broker deals with either Epic or Microsoft to compensate for declining sales figures. Rather, both companies have been aggressive about trying to get more players to use their services, and Rockstar's games are a reliable draw in games right now. If most additions to Game Pass or freebies on the Epic Games Store amount to nice bonuses, Red Dead 2 and GTAV are main attractions that are likely to pull in the players who just haven't bothered with Epic's digital outlet, or Microsoft's subscription games service.