Duty-free products are meant to meet you at the jetway as you board. I find it pretty annoying how the product cart often isn't there when the plane starts to board. This is usually because the duty-free kiosk is manned by the same person who has to wheel the cart to the gate and s/he is too busy helping customers to find time to deliver the purchases.

So unless there was some guarantee that I'd be refunded my money if the food/product didn't reach me, I wouldn't trust it, due to the issues I've had with duty-free.