Order Entry succeeds using Primary UOM despite Item being configured with "Pricing = Secondary"

I am testing a Dual UOM scenario and am encountering an unexpected behavior regarding UOM restrictions between Product Information Management (PIM), Pricing, and Order Management.

Scenario & Steps:

1. Item Definition (PIM): I defined an item with a Primary UOM (e.g., Ea) and a Secondary UOM (e.g., Box). The Pricing attribute on the item is explicitly set to "Secondary".
2. Price List Setup: In the Pricing Administration UI, the system allows me to add price lines for all UOMs across both the primary and secondary UOM classes. It does not restrict or warn me when I add a line using a Primary Class UOM.