If Epic lets players control money for their creations, they will likely work tirelessly to pump out their maps or objects to market to one another. Okay, they likely could not promote a Mario Kart course or re-creations from some other games (such as this Connect ), but gamers are already interested in what their counterparts are making. They've asked Epic for the functionality to save and share their barrier courses and constructions for others to experience. And should the studio expands the game's creative toolset, the neighborhood could sell other things they already (indirectly) spend real money on, such as character skins or weapons. This might be quite lucrative for Epic, also: Between 2011 and ancient 2015, Steam Workshop founders selling mods, cosmetics and other extras brought $57 million. Since content manufacturers get just a 25% cut of the sale price, that signifies Valve pocketed $171 million. (Hopefully Epic would honor fortnite items payment commitments to founders, something Valve has not consistently done.)
Even if the permanent Playground style came out mostly unchanged from its first test version, creators could probably make a mint on customized maps. But there's nothing stopping Epic from adding lots of pseudo-developer tools to tweak environmental effects and world factors. Players may use those to create their own custom modes, or even their very own mini-games. The half-game, half-development platform Roblox is set up like that to promote its players to make new locations and experiences -- and promote them to others. Out of a documented 64 million players, more than 1.7 million are founders who have been expected to make $30 million over the span of 2017.
Epic could say the same about Fortnite, which owes a number of buy fortnite materials success to a rabid streaming community that allegedly helped it become the most watched sport on Twitch. Assuming that Fortnite remains popular when the permanent Playground mode comes out, the game's streaming legions will most likely cover all the new maps and experiences players create.