I used Apple Pay to pay for a purchase on the Walgreens website in desktop Safari and yet the email receipt I received from Walgreens displays the last four digits of my actual card number. I checked my settings on my Walgreens account to see if somehow I had previously entered my actual card number as a payment method directly on the website, but I had not. How or why did this happen? This doesn't seem like expected behavior. How did they get my actual card number if I did not enter it?