All the bakery, dairy and floral items are provided locally, not nationally. There are different "Fearless Flyers" with different products in each US region.
There have been numerous posts on the chains board about how Aldi is owned by a family member but is not part of the ownership of TJs.
The buying power is limited in that they get closeouts and divide them among all of the stores. (an example from an old FF is : "We bought up the last 3000 pounds of this product and so each store will only have about 350 pounds to sell") The 'store brand' items (Trader Jose's, Trader Josef's, Trader Darwin's et al ) are pretty much nationwide, however I noticed the only TJ tartar sauce sold in Southern California is flavored with jalapenos and the only tartar sauce available in Michigan is plain tartar sauce under the same TJ label, so each store is not at all an exact copy nationwide like some mass marketers.