When an E-4 calls me "hey" or "hey man" knowing that I am an officer, should I bother to correct him?

You're on duty 24/7, on base , off base, uniform or civilian clothes, the unit patch being different or the same, rhe only thing that matters is an enlisted person showing the officer the respect, and its not showing the person respect, it showing respect to the rank. If respect isn't shown, it's failing the system and eventually the system won't work. Yeah, let him know.

I agree with SFC Casey O'Mally below. Make the correction and move on. You know if this conversation was observed by another NCO or Senior Officer, most would have nipped that in the bud, right then and there and perhaps even notify his first-line supervisor. Then they can take appropriate action if they feel it is warranted. Personally, I would make the correction and move on, I would only consider writing it up if it became a habit and I observed it again. This is all about Good Order and Discipline.

Absolutely, and immediately. Doesn't have to be a confrontation just a serious reminder of what the customs and courtesey's of the service are. If his lack of respect persists you may have to take more official action. It is not just his lack of respect for you it is a lack of respect for the chain of command.

That officer needs to see the current definition of " fratinization" I was an officer in the Army. This thing call wokness has changed the military. If I were on active duty,I would probably be on trouble for I am old ways of military.

There is no way for them to know if you're not in uniform. Unless you're willing to spend time correcting everyone who refers to you as "hey" outside work and out of uniform, it's not something to bother yourself about

I hated when officers would call me or other SNCOs by first name, especially in front of troops. Your problem is easy. Much stickier when officers do it to SNCOs. Abolish all 'familiarity' up and down the chain. It just turns into a shit show.

I was an NCO, in the army. You most certainly should correct the behavior. The first time a reminder that you are an officer in the military. The second time put it in writing.

My first duty assignment after OCS was as a training officer in a basic training company so I quickly developed the correction on the spot habit of not accepting failure to perform.to standard. You are not on officer or NCO to be popular but to be a respected leader.

Officer or not, SPC or not. I am 1-sided on this, mostly because I absolutely hate the word "hey". My family, my friends, coworkers, everyone that knows me, know that I do not respond to "hey". If I do respond, I promise it is not in a nice way. I have a name, use it.
Even if you do not have a problem with it, If the wrong person were to overhear it, it could be trouble for you and/or the SPC. I would correct it.

I've been out of the Corps since 1993, got out as an E5. My Uncle was a retired Ait Force Colonel and from the day I graduated boot until the day he passed, I addressed him as Sir. Flash forward to today. My nephew is a Major in the Army, he too is addressed as, Sir.

They earned it!