It's parasitic because if you want to participate in the market, you need to use their platform. Their value is ideally keeping scammers out, but they don't do

It's parasitic because if you want to participate in the market, you need to use their platform. Their value is ideally keeping scammers out, but they don't do a great job of that and part of the reason they don't is because they also profit when the scammers do. For example, gambling for kids (loot boxes) is OK. The other part of the value is having a central place to list and promote apps, but also there they're double dipping as you need to pay them to get eyes to your app. Their value absolutely does not equal 30% of your revenue.