The real issue is how many people know about the DRM? You figure joe casual gamer isn't going to be as informed as people like us. Anyway, they'll be figuring it out damn quick. The funny thing is you can imagine how the poor retail clerks are having to del with irate customers returning games when most store have a no return policy on open games.
If I wasn't aware of the DRM, than brought it back for a refund or exchange and they said no, I'd go ballistic. I'm certain we're going to see several class action suits against retailers and Ubisoft before long, and rightfully so.
How long before Ubisoft crashes and burns at this rate, I wonder.
That's the policy of the retailers. They do it to presumably to prevent themselves as being used as a source of piracy. Pretty much the same reason why they stopped renting PC games many years ago.
However, I do believe that the policy is you can exchange opened software for another copy...so perhaps you should just keep taking back newly opened software and telling them "Nope, this one doesn't work either" until they finally cave in and give you a refund or store credit.