Don't just talk about soda. The entire alcoholic beverages industry and the ethanol industry are massive producers of CO2. When any carbohydrate (corn for ethanol, for example) is fermented to produce ethanol, the reaction emits a prodigious amount of CO2. CO2 is what provides the fizz in beer and sparkling wine.
But, for those who don't understand the process, the CO2 was taken out of the atmosphere, stored in the plants as carbohydrates, and released during the fermentation process. Plant CO2 is just recycled.
The only 'new' CO2 is that released by burning coal or oil taken from the ground or by breaking down minerals/chemicals from the earth that have stored it for ages.
Where did the co2 come from, though?