There are no other things to use telegraphs or pony express companies for either. Or film camera's for that matter (thus why Kodak is in such financial trouble right now). Should we really block innovation just so older companies don't go out of business? If we did that, we'd never get any of the new companies that contribute large amounts of money and jobs thanks to their innovations.
Seriously - Walmart innovated by having large rural stores. That was such a success woolworth's went down and Walmart became one of the biggest companies in the country. That's the way the market works...