As mentioned in other threads, I have over the past 20 years brought tequila, special redwine or real champagne on board domestically and Int.(the latter especially when flying with Ms. Duck domestically). I have never had problems having it served. The trick is to hand it over to the FA and kindly ask her/him to serve it which with a brief explanation has never been a problem for me. I have purchased tequila on international flights and had it opened and served by the FA and even had the FA on a Kuwait Airline serve me a red wine I brought (in FC) as Kuwait Airlines otherwise is totally dry!! I have never consumed anything alcoholic on a flight not served by a FA.

(However, I have never tried it in caoach)