Just curious, but why not? Part of the cost of the upgrade to CL is offset by paying less for your dining, IMO. Breakfast at least is covered. Unless you eat a LOT, the dining plan along with CL is way too much food - for us anyways. The appeal of CL is largely centred on the convenience of the lounge with its food and drink offerings. (FYI: The CL rooms are the same as the non CL rooms. They are even often on different floors from the lounge in AKL.)
If you are staying CL you will have the food/drink offerings in the CL which reduce the amount of these that you will need to purchase, rendering the dining plan an expensive choice, IMO. We find that we sometimes only purchase one full meal at lunch per day when staying CL. A light entree or QS snack in the evening will often be sufficient for dinner along with either the appetizers and/or desserts served in the CL lounge. (which of these we partake of depends upon when we happen to be at the resort as these are offered during set times). OR we have a large breakfast in the morning in the lounge and don't eat again until a nice dinner out in the evening.
A room only discount on a CL room works better for us than Free dining. However, there's often only 2 of us and we eat lighter meals than those often served at Disney, so we only buy one regular meal and a snack/light QS per day OOP. Breakfast is in either the lounge (CL stay) or sometimes just coffee on the balcony in our room (reg room). We do the math to determine which type of discount works best for us. It is easy with all the information available online.
There its a CL focused thread here in this forum that you might enjoy. Lots of friendly folks over there willing to share information and tips to enjoy a CL stay!
Enjoy!