As far as street gangs in GTA San Andreas go, the GSF are depicted as more honorable than their rival gangs.Coming from a background of older traditions, they are against hard drugs being sold on their turf as opposed to the Ballas and Vagos.The Families also have a history of a traditional, intense, and bloody rivalry with the Ballas.Specifically when the gang war started is unknown, but the rivalry between the two gangs was in full swing as early as 1987.The fact that Sweet insists the gang shouldn't deal in narcotics, the deaths of OGs such as Tony, Big Devil, and Little Devil, and the abandonment of OG's such as Big Bear and B Dup has largely weakened them from their previous dominant position in Los Santos.Likewise, the splitting of the Grove Families into different enemy sets - the Temple Drive Families and the Seville Boulevard Families has massively increased violence from within the families and further weakened them.
Their unwillingness to enter the drug trade has dragged the Grove Street Families out of prominence in the years leading up to the game's storyline.
They likely also controlled Willowfield due to Emmet's presence there; specifically the Seville Boulevard Families.
During the beginning of the game and upon Carl Johnson's return from Liberty City, the Grove Street Families are the smallest, least powerful and least influential gang in Los Santos.
If the player sprays over all tags in Los Santos, they will wield Desert Eagle, MP5, and knifes instead.
They can occasionally be seen smoking marijuana and drinking malt liquor while talking and hanging around in groups.