Many people own stock in all sorts of companies without knowing anything about the actual business. They hold based on it being in an index or a margin lending list, historic share price performance or simply due to a decision to buy stock in all companies meeting certain criteria operating within a particular industry.
In short, there would be plenty of shareholders who had no idea that NMS even had any ships, let alone that they were idle.
People that use forums like this, and hotcopper where warned by a couple of posters about the situation. Thats why forums are useful, and you should always try and do some reaserch if you own shares in a company. Dont own shares if you dont have any time to devote to reaserch, its doesnt work, unless it is absolutely only blue chip.