People have done without bacon before, for sundry reasons. Shortages in World War II prompted the production of "macon" (cured mutton belly). Kosher-oriented families often opt for "schmaltz" (rendered poultry fat) or "gribenes" (crisped poultry skin).
Healthier options have emerged, but few have found widespread appeal. Sizzlean caught on for a while, but disappeared in 2005. Vegetarians can try "facon" from Morning Star and other brands. Anyone who has tried the South Beach or other diets is probably familiar with turkey bacon, which is bacon lower in fat and calories, not to mention flavor.
One option advocated by some foodies: Put a drop or three of liquid smoke on any bacon substitute.
Still, said Minnesota Flavor blogger Jason Kallsen, "I don't feel there is a good substitute right now. The smokiness and cured flavor is something Americans not only are used to but react to, as well. You say 'bacon' and people intrinsically know the smell, the taste, the use. Say 'bacon-like' and they get confused."