There are already plenty of sites that do this exclusively online for the same/cheaper price point. It'll be interesting to see if a store-front will be a good investment considering the high overhead cost.
I imagine they hope people will go to these stores for the same reason they go to Apple's retail stores instead of just shopping for Apple products online:
1) Immediate gratification. Sure it takes less time to order prints (or Apple computers) online and then get them out of the mailbox, but if you want a print (or computer) fast without waiting for shipping you can just drive to your local store and 5-10 mins later walk out with a purchase. There is a lot of value to that.
2) "Genius bar" The article states that there will be people who can provide photo editing help and advice in the store.
3) The "cool effect". If you post on Path, or FourSquare, or Facebook that you are at an Apple store you get a lot of "likes". (At least in my peer group) It's a status symbol to go to an Apple store (and Starbucks is the same way) If Polaroid can pull off this same image with their stores which will have a similar clientele they have a guaranteed money fountain.
I'm not so sure that there's an analogous Genius Bar for photo editing because the audience* doesn't care about real editing.
It seems like modern consumer photography has deteriorated to the "filter = art" style and most of my friends (20-35 demographic) don't seem to spend time doing things like contrast & lighting adjustments. I still do, but only for photos which will make it out of my Lightroom or iPhoto library which accounts for maybe 5-15% of what I actually shoot and keep.
*Perhaps the audience is predominantly outside my own 20-35 demographic and I've made a bad assumption; it's early to tell.
