@idontgetpaidenoughforthis
I pay for a 5 profileNetflix, all my DCs and my parents use it which takes up one each and no spare. So it bothers me if someone else has access. You can't watch on same profile at the same time and it messes up your lists.
My DCs aren't allowed to log into anyone else's device anymore- So never at girl or boy friend nor friends houses .
On the very rare occasion I have agreed they could -they have texted to ask me, logged in without friend seeing password, watched on their profile , then they log out of our Netflix account on that device once film is over. Most their other friends have Netflix so they don't need to. Also DCs have ourNetflix logged into their phones and laptops so they use those to watch which is what I say usually.
I change the password if any unrecognised devices show as watching and logged in on my Netflix or any streaming TV account (when logged into website).
If they break my rule, DCs aren't then told password again, they lose Netflix for few days (usually until someone explains!) and then I log their devices back in with only me knowing password for few months (meh, then I relent and tell)
I am harsh because I had 10 houses of friends/ (rich)ex H watching my Netflix account due to my DD logging into everywhere and giving password away and it caused all sorts of problems. One of DDs friends thought it'd be fun to (teenage) change all our profile names and reset all the languages for late night "prank". It took ages to undo it as the instructions were set to Russian, German etc
It was never happening again. I'm not being 'tight', I have limited money, people can buy their own and not steal a service I pay for. Nor ever mess up a service I pay for.