my short time in corporate america has taught me many things. one of them is that white guys treat greetings like military salutes. not only do they think they're officers, they think they can be shitty officers. you approach each other in the hallway and expect you to say hello to them with zero expectation that they should say hello to you in response. having them initiate the hello is heretic. once they get into that pattern i just stop saying hello at all. that's when they complain to your boss that you aren't being friendly enough, not being hostile, nut being unfriendly, but not being friendly enough. they feel entitled to receive friendliness but never give it. they treat this lack of excess friendliness as if it's plain old hostility. this is despite the fact that he's outwardly hostile to you whenever a white female intern or secretary half his age makes small talk with you in the lunch room. his real hostility is ignored while your imagined hostility is responded to several times a day.