I love RPing as a smoker, and making regular trips to the convenience store to grab a pack of cigs. I think it would be awesome if they could be actual items to use that reduce stress, and maybe make you hungrier/thirstier. Maybe even have nicotine addiction? It’s also fun to ask people to bum a cig or give one to somebody to start a conversation.
This might be something to come with the EMS rework, where alcoholism, drug addiction, etc will be introduced.