I have two friends.
One of them works on a farm and he gets paid by the farmer.
One of them doesn't work, but I get him to do jobs for me and give him some money.
They live in my house.
The one who works on a farm pays me some of the money that the farmer gives him.
The one who does some jobs for me doesn't pay me. That's fine, because he does some jobs for me.
I guess everyone thinks that's fair? I hope so. I think it is.
I have another option. I can pay the one who does jobs for me as much extra as the farm worker pays me. Then he can give me it back.
That would be equally fair, but fairly stupid from both our points of view.
Unrelated, people who work for the government think they pay tax in the same way as ordinary people do. Same goes for people on benefits.
I'm saying nothing.