text: Jumping into this old note - a lot of CO state parks do use boundary=protected_area and protect_class=4-7. These may or may not be joined with a leisure=park tag, depending on how people use the space. I don't see an obvious reason why boundary and leisure tags would conflict with each other, so I have added some to Clear Creek Canyon Park, Mount Galbaith Park and the conservation easement. Take a look and tell me if you like how it looks.
  
  As for whether or not the lines are "real", they are in a legal sense - for those not familiar with life in the west, our lives (and property lines) are dominated by the township and section lines of the PLSS, so there are very commonly giant straight lines dividing things. This is in contrast to the east coast where the property lines are older, and tended to follow natural features. Now if you are arguing that all boundaries are inherently imaginary, then I'd agree, but only after two beers.