Mechanism to Track “COSTS” associated with FREE SHIPPING Promotions

Question

Currently, if/when a merchant sets up a FREE Shipping Cart Price Rule - the Quote and Sales-Order tables (sales_order / sales_order_grid / quote / quote_address / quote_shipping_rate) capture cost associated with the FREE Shipping method as ZERO DOLLARS.

But, the reality of the matter is - the merchant still has to pay the Shipping_Carrier money to generate the shipping labels needed to actually ship the item.

Therefore, from a Cost-of-Customer-Acquisition and/or Profit-&-Loss-Statement (P & L) perspective - it makes sense to identify and/or track how much money it costs to "make the sale" w.r.t Shipping-Incentives.

Given this background, is it possible to setup Cart-Price-Rules to apply the Shipping Amount (i.e. as quoted by the Shipping Carrier) as a $$ Discount instead of accounting for it as a ZERO dollar Order Attribute?

In Other words,

How do we go from the Current Model:

• Order Subtotal => $30.00
• Taxes => $9.00
• Shipping & Handling => $0.00
• Order Grand Total = $30.00 + $9.00 + $0.00 => $39.00

. . .

To this Model:

• Order Subtotal => $30.00
• Taxes => $9.00
• Shipping & Handling => $17.00
• Discount (Shipping & Handling) => $17.00
• Order Grand Total => $30.00 + $9.00 + $17.00 - $17.00 => $39.00