Why do we tend to refer to our Grades instead of our Rank?

Coming from the Marine Corps to the Army Reserve the first thing I noticed, and was annoyed by it, was that every one just referred to themselves as "sergeant". They didn't use their full rank. Then I noticed they would mention their pay grade to let you know which sergeant they were. I just assumed it was an Army thing. I always felt if you are wearing the rank you earned the rank. Be proud of that rank.

Army command policy is very clear on how to address other NCO's, mostly is ego that gets in the way on how to properly address each other, worse is when senior NCO's call each other by first name

No issues or discussions brother. I'm around both military and DoD civilian personnel so we tend to be respectful to eachother. My new Amn coming in understand the value of discipline and respect of rank. I do my very best to keep the atmosphere around my shop relaxed and cool. Let's face it, I work in a high pace environment here in Okinawa. I think everyone who's been here knows how busy it gets. So I keep my Amn focused and ready to start the day. I just think people have too much time in their hands finding the things that are wrong, instead of finding ways to fix or mediate them. Control what you can control.

SFC Squires, what do you think about his statement? Do you agree or disagree?

What the CAPOC CSM is referring to is simply following regulations. AR 600-20 dated 6 Nov 14: paragraph 1-6 c. "..the numerical pay grade will not be used as a form of address or title in place of the proper title of address of grade. A Soldier holding the numerical pay grade of E–5 will be addressed as “Sergeant,” not as “E–5”.

He is exactly right.
An NCO can't be an NCO, if he acts like a SPC 5...

as a lowly SSG in the Bde HQs referred to myself as a Pvt E-6

Some of the problem in the Army may have started when they added the two super grades (E-8 &E-9) in 1958 and reduced enlisted ranks by one paygrade but let people keep their stripes. This resulted in two different ranks having the same paygrade. As a result in the sixties an E-6 could be either a Staff Sergeant or a Sergeant First Class and a Master Sergeant could be either an E-7 or an E8 depending upon date of rank. Same thing at lower ranks until promotions and retirement fixed the problem. At Ft. Jackson we had lots of E-7 Master Sergeants and E-6 SFC's. Add to that the fact that frocking was extremely common in some units and and there were a hell of a lot of people whose rank and paygrade did not match up. The Specialist ranks added more confusion. The Army made it worse by stating in the regulations that within the Army all specialists ranked between PFC and Corporal but when dealing with other branches paygrade was to be used to determine who outranked who. As a result of all of that many Army forms asked for paygrade. I realize that time has cured much of the confusion but by by then people were used to using paygrade. Old habits tend to stick around even when there is no longer any reason for them.

I agree. But those of us who were Sp5s and Sp6's (darned few of the latter) could get kind of shut out. They should have gone to the present system in the 50s and 60s. "Specialist" sounds dorky, especially when you were in an NCO slot, as I was three times as an Sp5.

Marines don't.