Have you done a practical of what you are saying. Go to a good exchange and place order of your bitcoin, make sure you choose the trending price and see if no body will buy. If nobody buy's bitcoin all the exchange would have shut down.
I am buying just not in huge volumes to make a differnce in price. This is my point ! Why are other people not buying at such a low cost its stupid not to. You would have thought that more people would be buying at the current low price. All the exchanges would not shut down It would take a while for them to stop wouldent happen overnight. You would slowly seen a decline like we are seeing with the minning rigs shutting down.