I agree that snobbery and N'ism are very different things.
One may find oneself on the receiving end of some pretty harsh stuff, where those with N'ish viewpoints, having no other hope of justification, resort to crying "Snob!" in vain attempts to validate rude or otherwise incorrect behavior.
Until one learns not to listen, or at least not to respond, one may try endlessly to explain why it would be polite or correct to do certain things. I count myself lucky, in that I now know that although the primary N'ish person in my life, my H, will never admit to doing something that is wrong, rude, incorrect, etc., he WILL take the information away and try to incorporate the change in his future behavior. But God help the person who wants closure, such as a civil acknowledgement that he understands and cares about what is being said to him about the matter. If it would entail any kind of admission of error, forget it.
Back before I knew how this works, we used to argue endlessly, as I sought to reach consensis. Now, I just do whatever I want and if I need his help I let him know. Eventually he will help me. But in days gone by, I wanted agreement, understanding, etc., based on an assumption that I could treat him just as I would any other friend or colleague in my peer group.
One of the first big issues, where H cried "Snob!" as a defense against me, was when I advised him that we needed to take the extra links out of the chain in our dining room chandelier. It had been looped up, held by a twist-tie for over a decade. This is a pretty nice home, and it looked really inappropriate. I told him that we needed to remove the extra links and push the extra electrical cord up into the ceiling. To my dismay, he insisted that it was fine as it was. I explained that since it would always be too long with the extra links, and that those would only be needed in a room with a higher ceiling, removing the extra links was just a normal part of installation. Perhaps the electrician had left it for the owner of the new home (H and his late wife) to adjust as they wished, base on their table's height, etc. We fixed it, but under protest from H, who called me "high maintenance."
This and many other items to follow became bones of contention, where H called me a snob, declared that he hated my family, because we're all snobs, etc. Any correction of his grammar got the same result. I was an awful person for caring about speaking correctly, and anybody else who did was too. I got sucked into the name calling, declared him to be "no maintenance" and eventually "white trash." I have stopped that now. When he tries to get things going, I just leave it alone. I no longer seek agreement at any price. I seek it only if it comes easily. If I have to go through too much to get consensis I just inform H of my intentions and go about my business. I can do whatever I want, regardless of what he says. He's often just trying to get that negative "banter" going that he did with his first wife. I don't like that game. I like to praise and collaborate. I like positive energy.
N's can be snobs, and they can also cry "Snob!" as they attempt to defend the indefensible.