Cost accounting is a critical part of management information.
Part of cost accounting is about getting data that informs decision makers about costs of business operations. This may be at the level of a part or a product, or aggregated for cost centers, profit centers, investment centers, departments, etc., all of which are rather similar. The key is to understand what they are doing and what they are costing.
If what they are doing does not seem to have any value ... then some further questions need to be asked and decisions made.
Corporate accounting systems usually have very effective cost accounting capability, but getting useful information from these systems is not always obvious.