I can see I may have to eat my words!
OK, I don't spend hours composing my feedback. As a buyer where the deal was very anodyne I'll leave something like "Nice simple trade, all ok". If the seller sends useful individual info I'll add to that "Excellent communication". Perhaps "Very well packed". "Quick despatch".
As a seller I'll mention if the buyer pays promptly and/or communicates well.
But I don't do much business, so individual action isn't a chore. If I start shipping dozens of parcels per day I'll be happy to leave just "Many thanks" to everyone and risk being despicable!