Yes curious as to the reason why? Even if the child is hungry when they get home they can give the snack then. The child isn't old enough to say they are still really hungry during the day so I find this request very odd.

Regardless of reasoning I would not do it. I once let a family bring breakfast as their commute was long. Never again. Other kids wanting food, junk being sent for breakfast, extra mess/dishes, extra time . Nope nope nope. My routine is my routine.