SnackNation is different from other subscription boxes, mainly in that it's not really designed for individuals but companies (they do have an "at home" service, though). What they do is put together a giant box of snacks for your office and staff and ship it monthly.
I don't work in an office environment anymore, but I would have loved to work for a company that had something like this. In the past, the offices where I worked either had nothing for food options, meaning you went out to get fast food or packed a lunch, or there were vending machines, but they were loaded with chips and candy. SnackNation is designed to give employees cheap and healthy options (and some companies even give the snacks out for free).
Because the boxes are designed mainly for offices or families, they do cost more than other subscription boxes (much more in the case of office delivery, but you are also feeding an office!). However, there is a great deal of variety and this would be a really nice benefit to help office staff eat better and also come together as a team. SnackNation gives you the option to try a free box to get a sense of what they do, so you can see it in person and get feedback before moving forward.