I was standing out in Union Square in San Francisco a couple of weeks ago. It brought back memories of my "crazy lady in Macy's" journey. This time, I was standing on the sidewalk in front of Forever 21. Capturing the looks of those passing by watching me use my phone to look at the shop window could have been more interesting than what I was capturing on my screen. I give marketers and retailers credit for pushing the envelope and experimenting with mobile technology. Unfortunately, it seems like we are not a LOT further along than we were a year ago. Some combination of the CPUs, GPUs, and networks cannot keep up with the tracking to overlay much more than 2D images. The experiences are triggered from a narrow band or library of symbols, graphics, and pictures.
Retailers shouldn't be discouraged from using AR; AR is a very good tool to facilitate the discovery and consumption of simple content.
I also believe that AR is well suited for entertainment and amusement - a good way to engage with the consumer base and offer an enhanced experience.
Also check out the Zappar t-shirts being sold; the cost of the service is low, with Zappar sharing in product revenue. Their time-to-market is short in terms of preparing the content. Their app is already in the app store - altogether, very low barriers to entry to use AR with your products.