Money & WorkFact
Why card payments cost you nothing but cost the merchant plenty.
Platforms serve two groups that need each other: buyers and merchants, passengers and drivers, readers and advertisers. Often one side pays almost nothing so it shows up in numbers, and the other side funds everything. With credit cards the merchant pays fees while you even get reward points. The price hides in shop prices.
Useful: If you pay nothing on a platform, the other side is funding you, and it recoups that.
Source: de.wikipedia.org