I think some folks went adrift with the "hay-is-for-horses" bit and got away from answering the questionfeel that it's O. My opinion (and therefore, only my own personal reactionK. to usage of the word "hey,") isuse "hey" as follows:
As a very informal greeting, I am not offended at all by someone using "Hey" for "Hello." Note: I would not use the term unless the person to whom it was directed was an actual "buddysomeone you know well," i.e. but otherwise, I would not use it with the local baker or dry-cleaning person, my mother-in-law, a professor, my doctor, or someone I just met, etc...you get the idea. But with my spouse, my good neighbor, my room-mate, my son, as a greeting, yes, And I thinkreally find it is actually a pleasant, very familiar wayrude to greet someone you are quite closeuse "Hey!" to. And bottom line: It's the tone of voice which tells the intent.
Another way get someone's attention in which I am very comfortable with the use of "Hey" isorder to interject it, for example, when excitedly introducing a (usually) positive opinioncorrect or observation about someone, OR even a negative opinion, but NOT ABOUT THE INDIVIDUAL YOU ARE SPEAKING WITH, eto reprimand them.g I feel it is an insult to be yelled at in that manner., "Hey Rather, that's a beautiful jacket you are wearing!" or "So youI think you goofed, but hey, we are all human!" And, "Hey! Did you hear they RAISED THE COST OF STAMPS AGAIN! (The latter is obviously not a slam against the person you are speaking with, but rather, a complaint or slam against "a system."
HOWEVER, past substituting "Hey" for "Hello" in a greeting with a close friend, and theorder to call someone's attention-getting soft remark of introducing to a nice thought or opinion, as described aboveperceived fault, there is one other use of the word which I feel is EXTREMELY RUDE! This is the use of "Hey" TO GET SOMEONE'S ATTENTION, USUALLY TO REPRIMAND OR SCOLD THEM OR TO COMMAND OR DEMAND SOMETHING OF THEM. Examples: "Hey! Turn down the T.V.!" or "Hey! Look at me! I am talking to you!" Or, "Hey! I'm over here (dummy)!" Or perhaps, "Hey! That's my pencil you picked up!" I take that particular usage of "Hey" to mean I am being "talked down to"should call them by name or reprimanded--again, it's all in the TONE OF VOICEsay, and is the equivalent of someone rudely grabbing my arm and jerking"Excuse me around to face them. Not nice, at all! And it actually makes the person who uses the word" in that manner appear to be controlling, rudea polite voice, and disrespectful...sort of like he/she never learned good manners or to respect others' feelingsthen proceed with whatever complaint necessary.