I was checking flight cost to CZM from DFW, it has been pretty high for quite a while. I was just curious so checked the same dates from Chicago. Cheapest flight I could find to CZM from DFW is $735 but if you fly from ORD connecting on the same DFW flights it is $281.
12/8 AA # 934 DFW -CZM then RTN 12/15 AA # 934 CZM- DFW $735
Compared to ORD to CZM with layovers in DFW and getting on the same flights
12/8 AA 2429 ORD - DFW, AA # 934 DFW -CZM, then RTN 12/15 AA 934 to DFW then # 2520 to ORD $281.
12/8 AA # 934 DFW -CZM then RTN 12/15 AA # 934 CZM- DFW $735
Compared to ORD to CZM with layovers in DFW and getting on the same flights
12/8 AA 2429 ORD - DFW, AA # 934 DFW -CZM, then RTN 12/15 AA 934 to DFW then # 2520 to ORD $281.