So if I buy or even say rent a carpet cleaner because I have a lot of carpet in my house and a friend asks to borrow it for a spill would it be illegal for me to let them use it? I throw in the rent because well that is closer to the subscription model. What about if I rent a Uhaul for moving my stuff and I let a friend use it to quickly move something either way I the renter takes responsibility. The problem with Netflix is there was nothing defined and they let it go on for years and years until they had a diminishing customer base and then suddenly there is a problem.
Not doing word play either just flat out not agreeing with labeling people as thieves when no theft actually happened whether by legal definition or not. Maybe by your standards you view it as theft, but do not label people as theives because of your opinion. If Netflix flat out stated over the years and years they have been around that the multiple screens were meant for single home use only then sure maybe ill be on your side with that, but nope they didn't they used the multiple screens and password sharing as free advertising.
Carpet cleaner: Would be based on the rental agreement. If there were no terms like "use by renter only" etc then you would be free to let others use it:
Uhaul: Same as above though I am fairly sure you would have to do all the driving.
Netflix: Their terms are clearly defined and have been for a long time. I believe they have had a "household" definition for a while now. Yes, at one point they tweeted basically in favor of sharing but they have changed their minds which as the owners of their content they are free to do.