There is something strange going on with the number of complaints against Sportsbet increasing. I am looking forward to what Sportsbet have to add in this thread, we need some sort of clarity.
You might be on to something but there is a little bit more to this because when going to the sportsbet.io website from the UK the URL gets diverted to sportsbetio.uk and there are lots of terms and conditions they have to abide by including very strict UK laws with them being based in the Isle of Man.
The UK site is FIAT-only, though. Perhaps they merely combined the various processes between the UK site and the BTC site, and the overlap was too stringent for general gamblers?
When it comes to multiple account detection, depending on the methods used, results may vary. And of course, the larger the player-base, the greater chance of false positives.