Certainly that was my understanding. I've never tried it however because ever time I find myself near a Disney Store, I've never got my shareholders card on me!.
We don't have a Disney Store near to us either, the nearest one is Southampton but I've been very disappointed with it in recent years, it seems to be all High School Musical or Hannah Montana and nothing I'd like to buy!
We're going to see Disney on Ice in Birmingham next month so I always make a little detour to the Disney Store there which is much better!
Yes, it is only instore. I had a query about something I'd ordered online so asked whilst I was on the phone. A great shame as so many items are online only.