LoL similar thing happened to me on Pinterest once. I got about 60 euros in my adsense account in just couple of hours.
I was like: wtf, where the hell all the traffic is coming from?
1000s of UVs in just couple of hours... So, I tracked down the pin and I saw it was repinned by Jane Wong... She had about 6-7 million followers back then I think. Did small investigation there and realized she's pinterest's co-owner's mom
So much power for one person. It's not fair
I guess she's one of the first who registered there and Pinterest was recommending her profile for all newcomers.
Unfortunately, she never repinned a pin from my profile.