So, at Shadow Behemoth, a mob of people were standing around for several minutes trying to get the interact with the node to mine it, but couldn't because someone's personal merchant got spawned on it. The use of personal merchants (and dare i say other interact-able items) over nodes/chests/etc., especially the special event ones is sometimes ridiculous. These nodes shouldn't be there, it should be an automatic box drop from doing the boss (just like the bonus box of goods). Trying to get people to back away so you could actually see the node to try and click on it was not working.
Anet needs to make personal merchants and other account only items so they cannot be interacted with by anyone but the owner.