Just putting forth a hypothesis here, but I wonder if we don't up our nicotine level higher than necessary when we first make the switch from cigarettes to vaping. It's possible that's what missing is the other stuff, but since we can't replicate that (unless we go with some of the other products like Snus), we try to satisfy that itch with nicotine and mistakenly just keep increasing the amount we vape. I started with 18-24 mg, depending on who I was getting it from and what they called high, but in less than two months I'm down to 6.
If I were truly addicted strictly to the nicotine, I don't think I could have made any of the plummets in nicotine that I have in such a short time. I do tend to chain vape, but I also chain smoked. But I also don't have any twitchy need for a cigarette, either, so the reduction in my nicotine has not impacted that at all (and didn't when I made the initial switch from 18 to 6 mg nic).
And just to be clear, I'm not saying I'm not a nicotine addict, but I think we maybe tend to go to extremes trying to satisfy the void left by cigarettes. Again, this is just me, but right now I find the quality and quantity of the vapor to be the most important piece in my non-analog regimen.