I bring back beer nearly every time I travel. I use both styrofoam packers (like the ones you can get from uhaul.com) or I pack with my clothes and a ziplock bag in my luggage. If you use a box though they will almost always ask what is in it. Southwest requires an additional heavy duty bag to protect against spills if something breaks. This was annoying but I was able to steal a baby seat water proof bag from them and I wrap that around the styrofoam within the box itself and it works. I have never had a beer break using it and it is so much better than UPS/FedEx, especially with free checked