How to handle missed customs and courtesies?

It happens, occasionally. Soldiers walk past, you are lost in your thoughts. In half a second you realize that your brain has recognized the double bars of a Captain! Oh no...absolutely disrespectful! Should I keep on walking and hope he or she didn't catch my name tape or run back and snap to salute?! *ahhhh!*
For instance, Capt (Join to see), the action that I would execute, would be to recognize my missed salute, and promptly, call over my shoulder, " I'm sorry, Sir. Good morning (or evening)!" I would absolutely stop and turn around. If you were to continue walking along, you would have heard me. If not, and you are expecting to correct me on-the-spot, I would already be facing you, and will render a salute anyway.
I've seen too many soldiers who put on their uniform and act like they are putting on a t-shirt and cargo shorts, like they forget where they are. Military courtesy should never be a chore, but should be a concept that a soldier should embrace, on the basis of what it means to be a service-member. A soldier who feels angry or resentful (or too lazy) to render a simple,basic military courtesy to their officers, perhaps should get out of the service when their time is up. And really, good riddance.

Poor CPL probably read "that thread" and is now confused as to who he has to salute, even if he has to salute.

I only walk on post when my CSM can come with me. I can't react fast enough if someone misses a salute.

Doesn't matter why. Sometimes people just aren't paying attention, but I will stop them and ask them if there's something wrong with their right arm and if they've seen the PA about it. Feign concern over their obvious medical condition which keeps them from providing the proper military courtessies and then tell them they should really have that looked at as it may end up hindering their career in the future. Usually wakes them up.

So my question to that is: what about in vehicles? Since decals went away, are enlisted exempt from saluting 06 and below unless they see stars on the front mount??

I've seen Sailors miss a salute periodically. Typically, the officer doesn't correct him, though he usually looks disgruntled by the time I'm close enough to salute. About a week ago I saw it happen, and I then caught up with the other Sailor; he said he was just distracted, and he was embarrassed for missing the salute, but he thanked me for telling him. This is usually how it happens if I see it happen and no one else is around.

Mostly, I see corrections being made by petty officers and Chiefs; these interactions range anywhere from a brief, "Hey, pay better attention, shipmate," to a full-blown chewing-out. The embarrassment level usually goes up when there are more chevrons or anchors involved...or anchors with stars on them.

It bugs me to no end to see things like that happening. It also bugs me to see ROTC cadets doing the same thing, or walking around with their shirts not tucked in, or walking around uncovered outside.

I've ran into this a couple times. If I realize the individual isn't going to render the salute, I simply offer them the greeting of the day and give them the chance to correct the situation. If they still don't salute, I stop them and talk to them about customs and courtesies as well as the importance of maintaining their situational awareness. I make sure to never come across in a way that sounds like a lecture. I see it as an opportunity to mentor. I remind them that there could always be someone junior in rank to them that could see them and accept their example, and that applies to everything they do throughout the day, not just a salute.

I guess it depends on the situation. A momentary lapse of situational awareness is not the same as a blatant disregard for customs and courtesies. I would generally say hello to someone who was passing me by without rendering the proper customs and courtesies...usually that was enough to get a salute. There were always those outliers who needed more than a gentle reminder, though.

Was the Corporal stopped and asked why they didn't salute? That's where I would have started on addressing the issue. If he did not have a valid reason to not salute, then that CPL would have been running to catch up to that Officer and fix the issue.