If you don't want people to know then get it thru the mail order. I am pretty sure they contract it out to a mail order pharmacy and the coming of generic Viagra has something to do with this.
I think it's most likely more so to combat counterfeit online pharmacies that sell Viagra. I was told that Viagra is the #1 most counterfeit drug in the US.
Reminds me of a REALLY embarrassing incident a few years ago......I got Viagra dust on my tie.........When it first hit the system we had Eastern Europeans come in with mucho cash and an Rx from some quack...they sent it in bulk to Bohunkia or wherever...