Things are probably going to get trickier in this regard shortly though once user accounts are made mandatory. Despite the BBC's claims, I wouldn't be surprised if this is step one in a plan to ensure all viewers have paid the UK TV Licence fee, especially following the recent closing of the loophole that allowed you to legally view iPlayer content in the UK without a TV licence if you didn't have a physical TV set.
(For those not familiar, UK residents are typically required to pay 147 quid or so a year if they own a TV or access the iPlayer service, which contributes to funding the BBC. Hilariously there is still a discount if you only have a black and white TV...).
https://www.theguardian.com/media/2017/may/11/iplayer-catchu...