If the airline staffer sees a big red bag with a wine bottle on it and the words Wine Check, I think they will figure it out.
I'm not overly concerned about the staff, but the other people in the baggage claim area.
It's not a big deal, just wish they made it a bit more like a vague cover. As they say in their FAQ section it has the same chance of theft as a cardboard shipper, but I feel they should offer a toned down version of it.
I do believe it's a great product, and hope they are very successful with it.