First off you did no wrong.
BUT if I am right you can place items on the ground AND they are guarded from others picking them up, there is also a option I believe to switch this off, therefore if you are disconnected the items should remain guarded for a reasonable time.
[not sure if it is.] This is a fault of the game and should be looked into.
Also depends why they were placed on ground in first place. Lets say one of the salesman[woman] has all there wares out on the table provided for such things, AND puff disconnected, free for all under rules tough matty you should not have put it on ground.
Again as this is provided by the game, so should be looked into.
Remember if you do not want to loose it, keep it in your inventory.
That is just my view.