I don't think people would donate many things (especially good things) if they don't have any way of knowing who its going to
it could go to someone they don't like or someone no one likes, who doesn't deserve it
if people are giving something away they can give to their friends, or announce in lobby and give to someone who whispers them
but the idea of making a random donation just isn't going to be very popular with players, and the only things donated will be bad items no one wants
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