I've heard before with shipping bottles to comps you can label them as "Food Samples". It's technically correct since by FDA standards beer is a food product and since you aren't selling them it's "samples". Probably just as fuzzy as "Yeast Samples". I think we use FedEx for things without having any issues. We ship samples all the time for cross country club vs club competitions. As far as I know we've never had any issues.