I can.. definitely see the utility here, but I would really, really like the option to turn these things off as well.
The map is already starting to get a bit crowded in places as-is, and even that aside I can see it looking untidy and I'm not even completely sure that, on the occasions I want to play as a gatherer, I'd even want to use the things. And that's setting aside that unlike most of the other icons, these are only really useful if you're a Disciple of the Land.
I mean definitely don't remove them (unless they went so far as to make the gathering nodes move about and finding them a constant part of the class gameplay.. which I'd think rather nice, but eh), but.. surely it'd be nice to be able to turn them off.
Hell, while we're at it, why not make it so we can go through the legend and tell it what icons and labels we do and don't want on out maps, in general?