They have also limited charges. I was trying to pick some Zinanthids on my alt and some multiboxer picked a freshly spawned herb and it insta despawned in front of me, even though I flew to it in less than 20 seconds which is supposedly the timer, probably even less than 5 sec because I was really close, but he was faster. So yes, multiboxers are the scourge of solo farmer because they can literally deny you a freshly spawned node. It's not guild wars 2 where nodes are truly personal and independent respawn for every player.
If 65g per anchor weed if rock bottom, what would you say about Silvermoon where it regularly dips to 47g.