An ordinary American male; joe, joe average, joe blow: Do you think that Joe Sixpack in Illinois cares?/ a sleazy bar where go-go girls perform for goggle-eyed Joe Six-packs
[fr the six-bottle or -can packets of beer these men typically consume]
The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D. Copyright (C) 2007 by HarperCollins Publishers. Cite This Source
Idioms and Phrases with joe six-pack
A lower-middle-class male. For example, I don't think opera will appeal to Joe Six-pack; he'd prefer a rock concert. This disparaging term, first recorded in 1977, conjures up the image of a man in undershirt and construction helmet who will down all of a six-pack (six cans or bottles of beer sold in a package) in an evening.