You don’t need to poke holes in the foil when you’re grilling, especially if you’re preparing food in a foil pouch. Steaming food in a foil pouch is a very popular grilling technique and one that allows you to steam your favorite foods in a matter of minutes. If you poke holes in the foil when you’re steaming food on the grill, then you’re allowing the steam to escape, which can lengthen the cooking time.