I think that's a myth. Sure macs are expensive, but if you look at top of the line machines running windows or OS X makes little to no difference in price. Granted apple doesn't sell new low end models.
But there's an easy fix: Get a used one. e.g. a 3 to 4 year old macbook pro is cheap to buy second hand by now and runs the latest OS X version (Mountain Lion) like a champ. Right now: make sure it has at least a core 2 duo CPU and it'll run anything. That's e.g. a mid 2009 MBP: it has a unibody (solid piece of aluminium housing the computer), they are sturdy and can take a beating. Pay a bit more and you can get an core i5 cpu and 4G RAM and it'll be a good machine for years to come.
None of those older macs have "gamer" performances, but they all can run Mountian Lion and anything else you might throw at them - even windows (I'd suggest parallels)