How did seller get my email address??

[flowermer]

I bought through Ebay. Did not leave Ebay. Asked a question to seller through Ebay messaging, he responded through Ebay messages.. But I also received 3 emails confirming my purchases to my personal email account directly from the seller. I did not respond. These were in my junk folder. I received the proper Ebay confirmations as well, like always.
So how did seller get my personal email??

Edit: And those emails were in my junk folder BEFORE I sent any correspondence at all. They arrived right after purchase of first lot. I then decided to buy a couple more things and messaged seller to alert to group items. 

[ypdc_dennis · Accepted solution]

The seller has buyer address and email contact information available from your first purchase. Before a purchase is made, no contact info (except through eBay's mail system) is seen by the seller.

Some people set up and use a different email for making purchases.

[reallynicestamps]

And you got his info too.

[flowermer]

OK. This was the first time we ever got direct contact from any seller not in Ebay messaging.
Thanks