I think it's perfectly within Wally's character to press the limits of what he can get away with. Besides, though he is frequently an apathetic individual, this would not be the first time he has expressed a tooth-grinding frustration directed towards the boss.
It seems... contradictory of Wally, who normally cares so LITTLE about anything, to yell so vehemently at his boss... It seems a little out of character for him.
Ah, earpiece headsets... mine is wireless, so it's even more unnoticed...
Anyway... I think it's funny that despite the fact everyone has them, no one notices the other person has it on.
Also, I think I could learn a lot from wally here.