The only ones that don’t have to give a 5% fee to Epic Games are big software houses that can pay a premium 24/7 support license for their games which means $500,000+ either yearly or per title as it was with UDK and before the whole Steam and App Store revolution and professional 3D Engines becoming cheap to use. What makes you think that big software houses would want to buy many assets on the marketplace? Unless they do some fake indie production and that happens indeed and so they wouldn’t use their own assets and employees for obvious reasons… But for their main titles they already have their own programmers and 3D modelers and so on. They rarely buy anything on developers assets stores.