When you create a custom product you can pick Kraft, Black, or White for 12oz and 16oz stock bags. Compostable bags are available on some 12oz/16oz SKUs when that option is in the catalog.
We use your color when that bag is on the shelf. We substitute when it is not.
These usually ship black no matter what you picked:
2oz samples
Single-serve cup boxes (the box is black; cups have plain lids)
Some 2lb and 5lb runs
Preset variety sample pouches
A black bag on a test order is not a failed custom label if you ordered one of those sizes.