Why should the seller compensate the buyer.

If I put a bag of apples in front of a donkey and it eats them cos I'm too busy talking to someone else does the owner of the donkey owe me the apples?

If you are out walking your dog and I put some food on the ground in front of it and then stand there chatting to you and your dog eats my food do you feel you should have to buy me replacement food?

They had not agreed a deal and the buyer was careless with his money. It  was an accident out of the control of the seller. He doesn't owe the buyer anything.