ATTITUDE IS EVERYTHING

It does seem, lately, that many people don't hear themselves. Appalled though you may be, you don't have to say a word. You could, but someone's feelings might get hurt. Some people don't know that they really DON'T want to hear what you have to say, and one more scintilla of their skewed viewpoints just might encourage you to start talking (and not stop until their faces are sufficiently cracked). 
Don't snap. Conserve your energy. Let them go off the deep end. No sense in you getting wet, too. Just wait. Your silence, patience, and compassion may cause people to consider that their harsh tone, thoughtless words, or crass approach are not the sort that encourage others to cheerfully and readily engage them--for substantial periods of time, anyway. 
I imagine that some people think that what works with one, will work with all. Some people will put up with crap, I guess. But then, there's usually a pay off called a salary involved. Others will offer crap servers a cheek to kiss, and it won't be one of the smaller, rosier facial ones.
What is it that makes people think that others have to abide their abysmal words and behavior? Where is the law they read that others deserve to be regarded as if they are less than garbage? How are they so appalled and confounded when people simply shut down, excuse themselves, or keep their distance? If they realize, (through prayer, or just the realization that no one is exactly tripping over themselves to spend time with them) that they ARE, perhaps, a bit arrogant, controlling, messy, strife-loving, snarky, pushy, accusatory, demanding, tactless, or bratty, they'll adjust--that is, if they really want people to give a darn. If they have an entitled, "all about me" spirit, that delights in talking AT, and not TO others, they'll keep wondering in vain why no one wants to be bothered. If they continue to demonstrate little concern for what may be crowding and running over on the plates of others, they'll continue running into brick walls; frantically wondering why others choose to ignore them. They will always conclude that their loneliness or exclusion is the fault of someone else. They'll never see that their most effective people repellent is staring back at them in their own mirror. If they're smart, they'll realize that no one likes drama queens or kings. No one likes abuse. If they're smart, they'll try a different approach-- a respectful, friendly, humble, warm, sweet one-- minus the attitude--and perhaps, they'll get the responses, support, and genuine friendships they're seeking. If not, they can continue to be perplexed by the sounds of crickets.