To pile onto the discussion, my thoughts are below...
-I loathe, but use the local UPS store. They are awful and ask 100% of the time what is in the package. I always respond "Olive oil". In fact, I may or may not have said that I make artisanal olive oils. I've shipped (sent beer) with them too many times to count with zero issues.
-Once I did receive a USPS package at my front door in a plastic tote. My prior Pliny contact in CA sent me a box of beer and one broke along the way. They were so nice, they even put the wet box in a big plastic ziplock bag. No note, no warning, just the struggling USPS doing it's job.
-I have heard that only the USPS would have a real issue with the shipment of beer, the other companies just see it as a slap on the wrist penalty.