You seem to be going back and forth between the general case and this specific case. When I&#x27;m talking about the specific case, you start arguing in generalities, and when I&#x27;m talking about the general case, you switch to talking about the specifics.<p>&gt; Accepting user registrations generally entails obtaining a means of contact which can be used to unlock an account whose password has been forgotten. By far the most common contact method used is email. GP may not have mentioned it in so many words, but the implication is trivial.<p>In this specific case, using your guessed-at reason for the need for registration, the implication that an email address is required isn&#x27;t trivial. It simply isn&#x27;t necessary at all. If it had been required, I also would have forgone registering. They have no need to contact me that I consider valid.<p>&gt; Requiring unique registration on a site also demonstrably results in significantly fewer people actually making use of the site. It&#x27;s perceived as a burden, and people not unreasonably wonder why they have to providing sensitive information in order to find out whether there&#x27;s anything there worth providing sensitive information.<p>Yet linking it to their social media or other accounts is not perceived as a burden? It is demonstrably percieved as a burden as evidence by both the other poster and myself. You also seem to be suggesting that linking a social media or other account is providing less sensitive information than creating a unique login. That may be the case at times, but I suspect, and I&#x27;d be surprised if you disagree, that usually you are providing <i>more</i> information by linking an external account versus a unique login.<p>&gt; And I think there&#x27;s a fair argument to be made that authentication via OAuth with a third party hits a sweet spot between user convenience on the one hand, and persistence and distinguishability of identity on the other.<p>I think there is too, <i>in general</i>, but not in this specific case if the only need is to have a unique identifier.<p>&gt; Finally, I&#x27;m really not sure why &quot;they&#x27;re tracking you!&quot; is such a concern in this case.<p>I&#x27;m not sure why you&#x27;ve gone from speaking very generally about the issue to getting very specific about the site in this case. I objected, very clearly, to identifying them as &quot;authentication providers&quot; <i>in general</i>. I never said anything about whether it was a huge privacy violation that they know you visited this particular site.