Free market merchant comments

Hi, just started the game not too long ago and made a merchant in the FM..
I came back to the game a few hours later seeing someone commenting in my merchant chat a cheaper price of an item.
But that person who commented also bought the item.
So was just wondering why would he do that?? Was it because I was selling something at a high price? (Although my item differs from his suggested amount of 10k+)

Thank you for any kind soul who would reply

From a very lost soul