combat awareness... is everyone deaf??

seems like every fight there was someone who would sneak NOISELY around, yet people within 10 feet would never heard them. I know audio is for the audience, but when an invisible lizard is right above you on creaky rafters, drooling and making gurgling sounds in an otherwise desolate environment, you are going to hear that stuff. These are HIGHLY TRAINED combat warriors??

i know i know its a fantasy movie, and I guess not for me, with people RANDOMLY growing random powers out of no where, so i should cut it some slack.