Did I do something wrong here? Does just standing by a rare mean you own it? I don't understand this game.
In my opinion, absolutely not. I don't know where people get this self-righteous idea that rares and nodes belong to them.
Yes, there's common curtesy - if a player is fighting a mob right on top of a mining node, I'll usually wait to see if they mine it afterwards. If I can help, I usually assist in downing the mob. If the fight is going on for a while, I'll say, "You a miner?" etc.
But you have to draw the line somewhere. And to be honest, if you're AFK, the rare or node is up for grabs.
Even when I have nodes or rares nicked from me, I just move on. Why? First come, first serve. Also, it might be just a case of screen lag, that when you 'zone' in, it takes a second or so, for the game to generate some scenery. It's not always rudeness or greediness.