Depending on the grind and coarsness of the kratom, the consistency of the powdered Kratom leaf can vary quite a bit in density. This brings about "guess work" in to the equation, with recreational justification leading to eat more "just in case" and caution leading to not ingest a proper medicinal dosage by dosing too low "just in case."
In any case, some different types of Kratom have been shown by other forum users to vary greatly in density through their pictures and anecdotes.
Although plain leaf Kratom is a weak, medicinal plant that doesn't absolutely
require a scale, it is always best to know exactly how much is being ingested to reach a dose that offers you just the right amount of relief you're looking for, without overshooting your dosage and getting more nausea/dizziness than you bargained for
Bottom line: if you can afford to eat Kratom, you can afford a scale. Kratom is a medicinal plant that deserves your respect, and in turn she will treat you well. I have been using it on and off since 2011 and it has kept me from developing an spiraling into an Rx opiate addiction during my injuries. During injury rehabilitation, I use it in conjunction with my doctor prescribed painkillers. I never take more than 3-5g a day for chronic pain, and when I'm in intense pain following an injury, I take half of my prescribed painkiller dosage to supplement it.
It is self-limiting and fulfilling, conducive to actually living life and being a productive, contributing member of society with a full spectrum of emotion, rather than the stumble through life in an apathetic, dulled, emotionally-flat painkiller-topia that comes with the territory of RX-opiates.
People have used this plant responsibly and medicinally for eons, and I hope people continue to use it in a safe and responsible manner with the respect it deserves.