In SAO the drops are assigned to the players who took part in the group with other players getting no knowledge of what dropped. There is also a bonus item for the person who gets the kill shot. I think this is also the case in other games based on the seed but that has not been brought up before.
Following the meal, the two began discussing ways of handling cases of rare drops in Sword Art Online, as the lack of logs tempted players to keep their drops a secret from their party members
I can't find the quote but in that series it is mentioned that the knights of the blood oath have a rule that who ever gets the drop gets to keep it.
Another point for this is that on the first floor boss at the end it is discussed that whoever gets the final blow gets a last attack bonus.
https://swordartonline.fandom.com/wiki/Illfang_the_Kobold_Lord
Illfang the Kobold Lord was slain by Kirito, who gave the final blow to the boss, and received the last-attack bonus item