Mslove ... go to urban dictionary.com and look up both 'brown bag' and 'brown bag special' or 'brownbag special' (without the space), and even 'chili dog'. I don't remember seeing a drug reference, but nasty none the less.
Ha, ha, ha you are all cracking me up here. Thanks for the laugh. I'm thinking that the phrase, "brown bag special" simply means a lunch special price.
I'm not even going to look it up LOL! I am perfectly content thinking it's the Brown Bag Special from Sonic. It it's really nasty then I don't want anything ruining my Sonic image ROFL!