A supplement to the soda is a revolving hot dog after a morning ride.  Size seemed to determine choice, it was also the only apparent difference  between the meat on the grill.  This is a fairly typical y available drink size, I can't imagine it being consumed in it's entirety.  I see it being ordered often.  

I believe that soft drinks are a reasonably cheap commodity and the only way to justify the price is to increase the size to inflated proportions.  There is a risk that consuming these may result in weight increase of a similar scale.  This may take some time for the boy in the photo, In the meantime he seems prepared for other misfortunes.