A young woman running late for a job interview realizes she's forgotten her lipstick. Minutes later, a 70-year-old steps into a store to buy some oolong tea and finds he's out of cash. Turn the clock forward to midnight, and a bachelor steps off the last train home wondering where he can find a bite to eat.

No problem. They can all easily get what they need -- whether cosmetics, an automated teller machine or just food -- at any of the approximately 36,000 convenience stores scattered across Japan.

Shoppers can pick from a number of chains, but chances are high they'll visit an outlet run by No. 1 konbini Seven-Eleven Japan Co. or its biggest rival, Lawson Inc. Together boasting nearly half of the total konbini market share, the two companies have spent decades carpeting the nation with their outlets to lure consumers away from supermarkets, department stores -- and their rivals' shops.