I've been camping since I was 7 years old. I'm still amazed at the places we went during the 3 weeks vacation that my Dad had each year. 60 years later, I still have vivid memories of those trips. During my working years after my Dad retired, he and my Mom traveled first in a TT and then in a 'C'. I guess its in my blood. The one place they never made was Alaska. So I made it after I retired.
I started with a 'B' and now have a 'C'. Washington and Oregon are still on my bucket list. And although I've been in all of the Northeastern states from D.C. to Maine complements of the U.S. Navy, I haven't camped there - yet. But I will.
In all that time, I've never met a grump while camping, but I sure did when I was traveling for work and staying in hotels. I was lucky to get a nod from a passerby in the hall or in the elevator. Maybe because we were working instead of playing.
When I get to a CG, I either sit at a picnic table if there's one at the site, or break out 3 or 4 chairs in case folks want to stop and chat. I also have a cooler full of beer next to me if somebody is both chatty and thirsty.
So if you're walking around a CG and spot a fat guy with a beard and a cooler next to him, nod or smile or say 'Hi'. If its me, you can join me for a beer. :)