We just did a Secret Santa beer swap on another brewing forum, and that's just what I did. Mailed it ground, and never said anything about what was in the package. Package arrived no problems at all.
I have sent my beer to a lot of competitions and to my family through UPS. I never had a problem. I bubble wrap the bottles and wrap in a garbage bag (just in case). I put the beer in a box with peanuts and then have the UPS store put it in another box with peanuts.
On the lable I put glassware and yeast samples. And that's it. So far so good...
The last time I sent beer to the brewcasters, I told them it was collectable beer bottles. The folks at the local UPS office know I ship art pottery and other collectable glassware all the time, so they didn't question it any further.