Conventional wisdom says competitors should lose sales. But new research from University of Tennessee, Knoxville, supply chain management scholar Seongkyoon Jeong suggests something far more surprising.

In a recent study published in Production and Operations Management, Jeong and his coauthors analyze a common tactic used in digital platform competition: giving away products to attract users. Their findings reveal that, in some cases, these promotions can actually increase sales for rival platforms.

The research focuses on the PC video game marketplace, where two platforms dominate distribution: Steam and Epic Games Store. Since its launch in 2018, the Epic Games Store has pursued a growth strategy centered on weekly promotions that make popular games free for a limited time. The expectation with such a strategy is simple: if gamers can download a title for free on Epic, fewer people should purchase the same game elsewhere.

But that’s not what the data shows.

Using sales data from more than 5,000 games and 270 promotion events, Jeong and his fellow researchers found that when Epic Games Store offered a game for free for one week, sales of that same game on Steam increased by nearly 60% during the promotion period.

In other words, a free promotion on one platform sometimes helps its competitor sell more.

The “Spillover” Effect of Platform Promotions

The research identifies this phenomenon as a cross-platform spillover effect. In digital marketplaces, promotions do more than change prices—they also increase awareness.

Platforms today host enormous catalogs of products, from games to apps to digital media. Many customers don’t know that most of these products exist. A high-profile promotion can suddenly bring attention to a product across the entire ecosystem.

Epic’s free-game campaign acts as a discovery engine. Gamers see the promoted title, become curious, and start searching for it elsewhere. That curiosity can lead them to purchase the game on Steam instead, even when a free version is available elsewhere.

The researchers describe this process using the classic Attention-Interest-Desire-Action (AIDA) model of consumer decision-making. Promotions generate attention first, then curiosity and search behavior, which can ultimately lead to purchases on competing platforms.

Why Consumers Still Buy

So if a game is free on Epic, why would someone pay for it on Steam?

The study highlights several factors that influence this decision.

First, platform ecosystems matter. Steam offers features such as multiplayer interaction, friends lists, and a broader range of downloadable content to enhance the gaming experience.

Second, the price difference may be less important than the network of players and products surrounding the game. Gamers often want to play with friends or access add-on content within a particular platform.

Finally, many users “multi-home,” meaning they use more than one platform. When promotions increase awareness of a game, some consumers opt to purchase it on the platform where they already play most often, not necessarily where it is available cheapest.

Implications for Platform Strategy

For businesses operating digital platforms—from marketplaces to streaming services—these findings challenge a long-held assumption.

Promotions are often designed to take market share from competitors. But in platform markets where customers can easily move between ecosystems, promotions may expand the overall market instead of simply shifting demand. That insight has implications for pricing strategies, promotion timing, and platform partnerships.

Strategic promotions can serve as a market-expansion tool, increasing product awareness and stimulating activity across an entire ecosystem. On occasion, this benefits competitors.

Applied Research in Platform Competition

Jeong’s work reflects the kind of relevant research, both academic and applied, that helps firms navigate today’s increasingly complex digital marketplaces. As platform competition intensifies across industries, whether gaming, retail, or logistics, understanding how actions ripple through interconnected ecosystems becomes critical.

The study offers a clear reminder: in digital platform markets, competition doesn’t always behave the way traditional economics predicts.

Sometimes, giving something away for free helps everyone sell more.

Access an online version of “Cross-Platform Spillover Effect of Promotion: Evidence from the PC Game Market” from Production and Operations Management. Learn more about the range of expertise present among UT’s highly regarded supply chain management faculty.