You mean Netflix and Amazon Prime Video...
That's not really a marketplace, which would have individual vendors selling their own subscription bundles.
You pay $12 to Netflix and you can watch it officially on 4 devices, which means it's $3 for any of your 4 friends, but you can "oversell" it actually more if you've some friends in different timezones. Many services work this way just fine. Streamwarez(tm) is here for a long time already.