A map (good, rough, accurate or ugly!) adds something to a gaming session - providing something on which the players can focus to help them visualise the world by which their character is surrounded. And a good floorplan in the midst of battle helps the players take advantage of cover, improvised weapons and a whole host of other creative goodness that might otherwise have been lost from a battle using counters on a square (or hex) grid.
I have produced all of these maps with Profantasy's Campaign Cartographer. I'm also happy to take requests and commissions (and not just for maps of Legend), so get in touch if there's anything you need.