First of all, these lists have nothing to do with war expenses. The war was over after April 1865. These lists are for excise taxes owed the United States Government.
The Internal Revenue Act of 1862 was enacted by Congress in July, 1862 and placed excise taxes on just about everything, including sin and luxury items like liquor, tobacco, playing cards, carriages, yachts, billiard tables, and jewelry. It taxed patent medicines and newspaper advertisements. It imposed license taxes on practically every profession or service except the clergy. It instituted stamp taxes, value added taxes on manufactured goods and processed meats, inheritance taxes, taxes on the gross receipts of corporations, banks, and insurance companies, as well as taxes on dividends or interest they paid to investors.
To administer these excise taxes, along with the tariff system, the Internal Revenue Act also created a Bureau of Internal Revenue, which created the lists to which you refer.
Using the full spelling from the 1865 Georgia lists, your abbreviations are:
R.L.D. = retail liquor dealer
R.D. = retail dealer