This concern is brought up at least four times in Proverbs, twice in this chapter. Compare this to verse 10. Look at how the idea is expressed in the early law of Israel.
(Leviticus 19:35 NAS77) 'You shall do no wrong in judgment, in measurement of weight, or capacity.Notice it is linked to “judgement,” to justice. This is the kind of justice that God is concerned with, not some vague notion of “social justice” which justifies using different measurements for each group. Using different standards to gain an advantage is cheating in the eyes of God. It is an “abomination” (8441). That is a pretty strong word.
So? A reminder to us to be honest in all our dealings. This applies to out buying and selling. It applies to our business and our social. It is to be a mark of the believer.