In Australia we have a long tradition of Swagmen. They were blokes in the old times who lived day to day, earned a living doing odd jobs from town to town and carried their worldly posessions in a swag on their shoulder or tied to the end of a stick. Some were treated a crooks - maybe they were? The famous Banjo Patterson poem/song Waltzing Matilda immortalizes the Jolly Swagman.OR (Urban Dictionary)
SWAG stands for Stuff We All Get, typically when attending an expo or trade show. You get SWAG when people at booths hand out free stuff like pens, prizes, etc.
Waltzing Matilda - Wikipedia
These days a swag is a type of canvas bed roll that you see young country people carry in the back of their utes. Some have mosquito nets attached but all have a mattress and are for sleeping under the stars (or on a friend's floor) in comfort. It's not gender specific - plenty of young women own swags . A good quality swag can last a lifetime.

