Posters are an opportunity to create branded collateral that customers might want to hang onto. You can also use posters as information collateral when you have too much content for a pamphlet, but you don't want to use a booklet.
Your poster could be a strategic counterpart to your product, like a delivery calendar for subscription-based products, or a habit tracker for workout equipment. Art posters are another option.
Customize the paper weight and finish so that your poster performs best for yours and your customers' needs. For example, when posters are included in ecommerce shipments, they are often folded. When posters are folded, it's best to use thinner paper stock and uncoated paper so the creases are less obvious after unfolding.