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

Seems to me it's a situational reaction. He apparently demonstrates good behavior in appropos places. If you see him in social situations what's the problem. I would discuss the matter with him, explain that in formal situations it is not appropriated to be less formal, in spite of your familiarity. If he disrepeects the situation, correct him for the sake of standardized address.

SFC O'Mally answered the negligence on your part correctly. It is your duty to correct a wrong!
Unfortunately we have to many examples of personnel looking the other way.

I was a USN tin can sailor (and we had somewhat less formal rules than larger ships, attitude adjustments were NOT part of the chain of command solution), if I had talked to an NCO with the word 'man' I could count on a 'counseling session' SOON! As you said, you change the line then that line changes PERMANENTLY. The last E-6 I worked for was 6'3" and over 275lbs (and was a member of the shipboard '300 club (as in bench-press that much))' if he laid hands on you, YOU KNEW IT!!! Sounds like you need to have a word with this young man, and if....then TAKE CARE OF THE PROBLEM!!!

With all due respect 1LT, if you do not know the answer to this question then turn in your bars.

Have you considered that maybe he didn't know how to address you 8n the circumstance? Are you so wrapped up on your RANK that you need acknowledgement 24/7? Get over yourself. Your rank only applies in the course of your JOB.

I'm thinking 'like a roman candle'.....then again, you can quasi lock him up...put him at ease - being out of uniform does not change the 'rank' situation - and since he knows, well, it goes without saying he should be reminded - roman candle wise or gently, its a matter of choice. I simply think what would I do. Even as an LTC, when I came up on someone I KNEW is senior to me, I simply do what I was taught...I render respect and whip it out. Besides.....how hard it is really?

If you have to ask ...... hmm.... you should know better just my two cents.... and you are a 1LT???

Just my opinion, but civilian clothes outside of work the Yes Sir/No Sir is a bit much. But he should address you by your rank not name and especially not a 'hey man'.

A reminder is definitely required in a situation such as this, given the significant difference in rank. However, the question is how to correct the "oversight" in such a way, that the message is clear, but mutual respect is maintained. One way to do that would be to put the SPC in your shoes, by quietly saying something like, "SPC, you worked hard for your rank and position, so I'm sure you wouldn't like being called just a grunt, now would you? Well So did I, and 'Hey man' bothers me. Please grant me the same respect I give to you." If that doesn't nip that slip of protocol in the bud, you can then (and should), lay it on the line.

As a senior NCO I would have lit into him like a bad smell on a turd. Never let a subordinate get away with disrespect like that. As an Officer you should never allow it. you don't have to lite into him just remind him of his position and warn him that further actions of this type will be dealt with harshly and follow through.