Years after P2P file sharing built the DPI industry (first for music, later for video), it appears that even paid OTT services are shared, and potentially a large portion of the popular Netflix traffic (see "Sandvine: NA Internet is Concentrated Around 3 Content Providers" - here) is not paid for.
Jason Mander [pictured] reports to globalwebindex that ".. Reed Hastings also announced that Netflix was considering ways of making it harder for people to share passwords – which GWI’s data shows to be a widespread trend. In fact, our new Q2 2015 figures reveal that almost two thirds of users in the USA and UK are currently sharing their account.
What’s perhaps most significant here is that almost a fifth of Netflixers say that 3 or more other individuals use the same account as them. When we’re talking about total audience sizes, that means we need to abandon the notion that 1 paid-for subscription = just 1 user. In reality, there are tens of millions of additional users and the likelihood of people taking this approach will only get more common as Netflix gets more expensive".
See "Two thirds of Netflixers share their accounts" - here.