No, there's no market risk because the inventory is closed almost immediately. As the inventory comes in they hedge using liquid LTC futures which are available on a number of exchanges. Or they just sell the LTC spot straight away. Either way, it is a trivial task that one person can do manually after a few days of training.

Either they hire that one person themselves or outsource it.

So they would just automatically sell the coins, as pizza234 suggested. Seems like you don't want a human trader and instead want an automated process automatically selling, considering that Wal-Mart is global and operates 24/7.

Yeah, actually I misread their second sentence initially, but that's exactly what I imagine they would do.