They (the people) used to buy grain in the upper part of the market in the same spot without measuring or weighing it. The Messenger of Allah ﷺ forbade them to sell it there before removing it.
كَانُوا يَتَبَايَعُونَ الطَّعَامَ جُزَافًا بِأَعْلَى السُّوقِ فَنَهَى رَسُولُ اللَّهِ ﷺ أَنْ يَبِيعُوهُ حَتَّى يَنْقُلُوهُ