I used to work at Starbucks and occassionally riders used the drive through. I guess it saves them the hassle and fear of locking the bike out of sight. As far as I remember they even got free drinks sometimes.
I assume Wendys is doing you a favor. They only give their obesity food to people with inactive lifestyles in cars. They saw the OP attempts to be healthy by riding. So they refused to give him that toxic food.