These “Free” postcard promotions come from Graze, a subscription-based service that sends out personalized snack boxes to...View More their customers. They've been using this free promotion since late 2014 after trying a $1 promotion. Graze has a very simple process. You go to their site, choose a select number of snacks from the 100+ available, submit your order and shortly after, you receive a box with all of your chosen snacks. Because the concept & process is so straight-forward, it makes sense that Graze decided to use a simple postcard. It’s a “free offer” that’s easy to understand & there’s not much need for a ton of convincing. Like many food-related items, delicious-looking photos help tremendously, which is why they made the right side of their postcards primarily for photos. Of course, Graze ran this free deal with the goal of converting first-timers into long-term subscribers. And they tip the scale in their favor by requiring you to put in your credit card info for the free box. That way, instead of deciding whether you want more, you must decide whether to cancel, which could be a tough decision if if you liked the snacks.