There's some planning when skiing (for reference, I ski at A Basin yearly too; great place), but I think this is a bit of an exaggeration. Usually it's pretty easy to plan, esp. at A Basin to say, "meet at the midway restaurant".

And from a technological standpoint, all the maps that you can have printed are all online as well, so in the same way that Yellow Book entries are now database rows, maps are either primitive PNGs or interactive terrain maps.