Samsung, among other vendors, still sells phones with GB right now in Brasil (and in many other countries, I guess). GB is the preferred OS for the cheap phones that carriers give for free in their lower-level data plans in my country. These phones never receive an OS upgrade.
The ugly truth is that device vendors and carriers don't care about market fragmentation. They just want to push those devices out of the door, regardless the harm they do to software developers. By the end of 3013 your apps will still need to support an OS released in mid-2010.