Well I'm over here from the "dark side" AKA Gladiator. Yes I wave at CJ, YJ, TJ, LJ,JK, JLs and low and behold any other Jeeps. I've heard from many this or that isn't a real Jeep like my MJ or XJs. Now after all the other Jeep's that my XJ has dragged out of being stuck then hearing it not a Jeep.
I wave at about everyone... Including Toyotas, land cruiser ect. But not the I'm to cheep to get a full lift kit and just jacked up just the front of my vehicle. . But that's the way it was where I grew up with being friendly that way.
I have noticed that many JK, JKU ect don't wave or even back when I'm driving my LJ. Heck yeah I wave what does it cost me to... Nothing and that can piss off the one's being a jackass too
Remember Life is Short and fleeting. Oh I've had my time to be a A.. hole there is a time and place for that too. But not driving.
I wave at anyone who waves at me. Whether in my jeep, SXS, walking down the street, etc.. We need more niceness in the world. If someone says hello, it's polite to say hello back.
Never understood the perplexation this subject brings no matter the variation. Just do whatever you fell like doing and do not get miffed if you do not receive in kind.
Nobody is going to write on your gravestone where you were on the subject.