That's very interesting. It's a fair argument, but sometimes, instructors for example want to protect their content and only share it with a person and they allow account sharing but limit it to one person.

but if gets out of control (as one company had 47 people sharing one account), that's plain rip-off and costs companies a lot of money. So it's a good idea to limit the number of devices. Many companies do that, for example Evernote limits how many devices you can use to access your own notes.

On top of that, you pay for 24 access to a device but companies would totally change the structure if they knew everyone would be streaming 24/7 it's a stats and chance game.

Also, not saying everyone has good intetions nor is everyone a bad actor. Manytimes it's just easier to share than add a paid user. Other comapnies allow you to share account for a discounted price. It's not a black and white situation :), but for anyone who wants to control or just monitor that, this library helps them.