Unclear on the concept

Today I won a prize in an online contest for Caribou Coffee. My prize was a free drink of my choice and I was informed that I would be notified via e-mail later in the day. Within the hour I received the confirmation e-mail which, I assumed since it was the result of an online contest it would contain the information needed for me to receive my drink. Instead I was informed that I would "receive your gift certificate in the mail 8-10 weeks after the end of the promotion. It will be mailed to the address you provided on the registration form. The promotion ends on April 7, 2006." So, enter an online contest, receive your prize (a coupon) about three months later. What's up with that?