Nielsen Research reports that more than 1,400 convenience stores across the company have closed since the end of 2007.

For those that are considering convenience store franchising, news of industry hardships may be disconcerting.

Yet convenience stores, which are almost equally balanced between independently owned businesses and franchises, still dominate the tobacco, ice and beer markets - in fact, convenience store sales of tobacco and beverages generate more than $90 billion each year, Nielsen reported.

Stores should focus on offering gas, snacks and prepared foods - the top items expected by convenience store consumers, according to the Nielsen survey.

"The key to success is innovation," said Tom Pirovano, director of industry insights at Nielsen. "C-store retailers need to constantly fine-tune their offerings in the face of increased competition from other channels while never taking their eyes off the basics of cleanliness and efficiency."

The success of franchises such as convenience stores is an important part of the country's economic health, experts say - every $1 million lent to franchise small businesses generates $3.6 million in annual economic output, said the International Franchise Association.