its more awkward if you wave to them too
I think it's more awkward when they are looking at you.
Also awkward when your staring in to space near their head and then they turn and think that you're staring at them :/
THEY ARE LOOKING AT ME. >:(
But if they aren't looking at you then they won't notice you looking at them.
But they do look at you, when they see you turning in their direction using their peripheral vision.