I'm pretty sure that Southern Hobby has to purchase CGL product from Alliance, the primary distributer of CG. Alliance will, in most cases, supply their own retail clients before releasing product to another distributer. Your FLGS may find that stock is available from Alliance directly. One of the biggest problems, IMO, for the FLGS these days is the distribution model. There are about 11 distributers of gaming product just in the USA including Games Workshop which is their own distributer. Some companies will make a single distributer exclusive for their product while companies like FFG will accept direct orders and cut out the distributer all together. The FLGS needs to decide how many different orders they want to manage in a week or month and what kind of payment deals those companies will offer.
They might get Net 15 from one distributer for weekly shipments but Net 30 from another for bi-weekly, then Games Workshop requires COD while FFG wants Net 60. All this on top of managing the pre-orders and requests of customers, OP, events, and every thing else.