Sorry, but I think account sharing is a valid social-lubricant and smart thing.
For example, I share prime and netflix with people...
The reason is that its "time division"
So, for example, youre paying for access to an account with 24/7 access to [RESOURCE] -- but you only personally use it for say 6 hours a day... but paying for 24 hour access... then who cares if it is me that logs in for 6 hours, and the tom dick and harry use the other 6 hours each...
you still got paid for the 24 hours of account access....
stop trying to tie every access to a single person.
I have been sharing accounts for over a decade.
If an account is paid for, GFYS.
So, account sharing, if its paid for account, is none of your business. What if I am supporting a friend who cant afford your service and youre helping out your friend?
you do not need to monetize every BODY you need to provide value to PAYER via your service.
so GFYS if you think that every individual PERSON who accesses your service "owes" you an account or payment.
seriously.
the ONLY argument against account sharing is if you don't have limits on SIMULTANEOUS how many individuals are logged on...
So - thats a better metric.
Real world example:
best friend is a dir at nflx, he has a son, a wife, a good friend and himself.
All live in different states and countries and continents.
He warned that they were going to crack down on this, but many people are like "I am a parent and I have two kids at college (all diff timezones, thus diff access times individually, given the account is active 24/7) and they should be able to access my account, why should each of them pay for access to nflx rather than "mom" just pay for an account and everyone login as we all have different schedules.
youre not paying for a user account, youre paying FOR TIME TO ACCESS WHAT YOU PAY FOR...
Why care for WHOM is accessing the account... its already paid for 24/7.
The policy should be around HOW MANY ppl you can share youre account with from a simultaneous access perspective. period.