Why does the 13inch non-Retina Pro still exist?

Here's the gist, its back to school season which means people are picking up new laptops everywhere. Many of my old classmates are posting picture online of their shiny "new" Macbook Pro which is the 2012 13 inch non Retina model (You can differentiate between that model and the retina one if "Macbook Pro" is etched in the bezel below the display). I've seen a bunch people pick these up and my only conclusion is that people aren't at all educated on what they're purchasing. Yes, it's true that the Macbook Pro was (and maybe it still is) the best selling notebook in Apple's line up and best selling Mac. It was the defacto laptop for starting college with. But the Macbook Air honestly has stolen that crown in the past few years (I'd argue ironically in 2012). I can't imagine all these people would still buy the 13 inch pro knowing that the Air has 12 hours of battery as opposed to the Pro's considerable less. That spec alone, makes the 13 inch Air the new defacto. What do you think? Why are so many people picking it up when Apple hasn't updated it in 2 years?