Wow I just read this today! Ironically, I was just in my SDM Optimum account today and so I know how easy it is to get in! I can't believe that it is not more secure (password needed) or something. Especiallly when these points can be used for GC which are like CASH! Every other loyalty program I belong to you need to register online and need a password to access your account!
That is just stupid of the person to do. I mean I don't shop at SDM much (I only have just over 1500 points but did that phone prescription thing to gain 2500 points so almost tripled up here!) so I know it takes a LONG time to amass over 300,000 points and that also means someone has spent alot of money there, unless they traded for some as well, I can't say for sure.
Bottom line is, this is despicable but am not sure how a court of law would handle this one. They are points, not merchandise... it would be interesting to say for sure.
Bottom line is, like others have said, if Shoppers won't protect you, then protect yourself and get a card as a backup to transfer to! I think I accidently opened a new account tonight so I think I am getting another card in the mail. I might do that myself!
I hope the person gets their points back. Bottom line, this is despicable.... but Shoppers makes it so easy to do.

