They cannot do anything in Georgia. It is relatively difficult for them to open and maintain a bank account, to get a residence permit (if they really want one), to find a job and to find a sympathetic landlord.
Many leave for Serbia. They are young and Western-oriented, and the lifestyle in Georgia too boring and too conservative for them.
Serbia offers them more with regards to a new home: they are welcome, they get residency, there are no problems getting a bank account, and prices are lower (for them) than they are in Georgia. The lifestyle in Serbia is much more open-minded, which appeals to younger folks.