Not surprisingly, none of those explanations is correct. Other acronymic explanations for it that we’ve encountered are:
it stands for “secretly we are gay”and most frequently used as code on posters announcing gay orgies. The term swag was invented in the early 1960’s by a group of gay men in Hollywood. “SWAG” is an old acronym that gay men used in the 60’s that stood for “Secretly We Are Gay”, and Swag was used as a label to identify and announce one’s status publicly. Yet that fact stops few from reaching for acronymic explanations for a variety of far older words, especially in instances where the true etymologies aren’t crystal clear. While many common terms have entered the English language as acronyms (words formed from the initial letters or syllables of a phrase, such as radar, which came from the term Radio Detection and Ranging), only rarely did that phenomenon occur prior to the mid-twentieth century.