In 1970 the Federal Trade Commission and the State of Calif stopped Luckey stores from expanding and opening a series of Warehouse stores called Gemco - why? because they had gained too much market share. Today there are no Luckey Stores. All the stores that don't change with the times get hammered. For every Albertson's that closes a Whole Foods will open...maybe not every one, but many of them. People want choices.
People do want choices but sometimes there is no choice. Think Microsoft and your local cable tv company. Just a couple of examples.