I have often thought of this too, daisybean. The solution that I came up with is like a glove compartment in each row of seats of each train that is padded on the inside and latches securely. These compartments really wouldn't have to be that big. Or they could actually out these compartment in the seats. That way the door wouldn't come open because of the body weight and nothing would fall out. As long as these compartments latch and are padded people could put loose items in them and they wouldn't fall out or get damaged.
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