Unfortunately, they are going through steem, likely with temporary phone numbers for the sms-verification.
As in almost all my cases, they are simply exploiting the steemit sign-up process with fake credentials. And that's also how they get their initial voting power, delegated by @steem!
Using anonsteem would require an actual investment, cheapskates like these take the free route!
I guessed they were not paying for it. Steemit need to filter out fake phone numbers
Unfortunately, that's probably almost as impossible as filtering out fake emails.
Does Steem use browser fingerprint with a machine learning component. It's very hard to keep a truly clean session and spammer patterns can be found quite quickly.
Looking at how much the steemit.com sign-up process is being exploited, I sometimes doubt that there's anything being checked at all!
Guy, are you still active here?
I need your expertise.
I know it's hard, but other sites have dealt with this too. I do wonder if all accounts should have to be paid for. Even a few dollars would deter such behaviour. I know that's an obstacle to poorer people, but Steemit could get overrun with such 'sock-puppets'. I just don't have the answers for this.
I'll probably discuss this with folk at Steemfest. It's an important topic
I think the proposed change in HF20 does have some potential by creating new accounts with zero voting power but a minimum allocated bandwidth without available stake instead.
At least this does take the incentive out of mass creating new accounts, but I am certain it also opens up some new exploits of its own!
I think there is plenty alternatives to charging people. The would deter most new users.