You explained the iMac or other consumer devices. It does not explain a purportedly professional device.
As I mentioned in another thread, I was seriously considering the MBP Retina as my first full Mac computer. Having a serviceable battery simply kills it though -- maybe Apple has some amazing new battery tech (unlikely), but my experience has been that laptop batteries start seriously degrading after a year. Despite all of the toss-away commentary in here by people with apparently more money than brains, I have household laptops that are 4+ years old and still working perfectly adequately as, for instance, web appliances. I refuse to spend $2200 for a laptop with such a short utility life.
And what's the deal with the non-retina costing the same as the retina? It seems like Apple is trying to heavily encourage getting the unserviceable model by overpricing the other model.