I'm not referring to any one specific scenario, but as a general UI design improvement.
Where ever possible you should looks for ways to convey important information to the user. For the same reason we put N,S,E,W on the buttons instead of just 1,2,3,4; utilizing the button text to convey additional important information. Since air spawns are a special case, additionally utilizing the font color and possibly a hover tooltip would convey the additional information.