You are correct, it allows for growth. Picking to lestagii 1 or 2 is in violation of the treaty between all guild able to pick lestagii.
The Rangers guild spent quite a bit of essence to get it replanted to those levels a while ago when this treaty was put into place not to mention the amount of work put into it by everybody doing the replanting and evoking.
Picking it to 0 in this case is detrimental to the growth of lestagii, yes. But it will hopefully show the person doing the constant overpicking that the rest of us with the ability to pick it will not just stand idly by when they line their pockets/pouches with lestagii.
For me personally it makes almost no difference as I haven't actually had large quantities of lestagii in years without getting it evoked.
And being the first person to it daily is impossible for most of us due to otherworldy issues.
Written by my hand on the 6th of Agamnion, in the year 1120.