This is a Google offering that only allows Facebook and Twitter sign-in. That's a bit odd; perhaps it exists for the purpose of getting people to opt their Facebook/Twitter info over to Google?
More evidence for this theory: here's what Prizes asks for via Facebook Connect:
…name, profile picture, gender, networks, user ID, list of friends, and any other information I've shared with everyone… Prizes may access my data when I'm not using the application.
The requester dialog only identifies as 'Prizes', not as Google, which seems a bit shifty. The Prizes 'Privacy Policy' says...
We'll treat any such information [from the Social Network Service] under this policy as if you'd given it directly to us.
It also links to the main Google privacy policy, which says (in far more words) that Google can use any info you give them to improve any of their services.
About a month ago, Google started showing me info here and there referring to people I follow on Twitter. I didn't understand at the time and still don't know how they matched up my Google account to my Twitter account.
The Facebook request details you're quoting are not unusual.
> I didn't understand at the time and still don't know how they matched up my Google account to my Twitter account
The information on http://www.google.com/s2/u/0/search/social can be informative for checking how Google links you with other people. Even if you didn't share your Twitter username with Google, I suppose that if someone on your contacts list shared their Twitter username, Google would be able to make the connection.
I didn't even have a Google profile until three days ago. I hadn't entered my full name, had not used the gmail to sign up for anything, have only exchanged 2 emails.
What would Google gain from such practices? Why not just ask you your facebook/twitter username upfront? Propally only a small percentage of their user base is ever going to use prices.org anyway. I think the story here is that it is done by slide, which still acts like it's an independent company.
What would Google gain? More opt-ins. Maybe more people are willing to opt their friends-list into a service called 'Prizes' with no Google branding than Google itself. Or even if not more people, a different set of people, who incrementally add info that would be harder to get otherwise.
The idea this is Slide showing its independence is interesting too, but why no Google/Google+ as even an option?
I think one of the potential problems with Google+ is that it is a "brand extension", too close to the parent brand, which already means something else to people. (To some extent, this was the problem with "Google Video" versus "YouTube", as well.) Maybe Google has empowered Slide to move full-speed ahead on a "Plan B", a network of many social sites unencumbered by Google branding. At the extreme, if all else fails, this could culminate in a new social network service by Google but under a non-Google name.
More evidence for this theory: here's what Prizes asks for via Facebook Connect:
…name, profile picture, gender, networks, user ID, list of friends, and any other information I've shared with everyone… Prizes may access my data when I'm not using the application.
The requester dialog only identifies as 'Prizes', not as Google, which seems a bit shifty. The Prizes 'Privacy Policy' says...
We'll treat any such information [from the Social Network Service] under this policy as if you'd given it directly to us.
It also links to the main Google privacy policy, which says (in far more words) that Google can use any info you give them to improve any of their services.