I don't know how Georgia operates, but I have heard of people being cited for possession in other states and not being arrested. According to questions people from Georgia have posted on Avvo, it appears that Georgia can cite people without arresting them:
The municipality that I work for (in Alabama) has an ordinance that allows a UNTC to be written for POM 2nd and MIP. Of course, it is officer discretion. The way ours is written, it doesn't matter if it's only residue, or a few joints. As long as it would otherwise meet the criteria of POM 2nd, you can cite for it. As long as they sign the UNTC, they are free to go. It is similar to what Panama City and Tuscaloosa have .