Why did i get posts in an email ?
If you've subscribed to a thread, you'll get email notifications you let you know that someone has posted in that thread.
i have not subscribed to anything but i got an email
for 10 threads.
I've gotten some too. It's something they started to show you the trending threads at that time.
There should be an option to unsubscribe from those email alerts at the bottom of the message.