HOUSTON -- Convenience stores are no longer the only destination for customers who want to make a quick grab-and-go purchase at any hour. The channel is facing increasing competition from grocery stores, dollar stores and more, according to a new report by market researcher The NPD Group.

For the quarter that ended December 2011, non-traditional convenience outlets such as grocery stores, mass market retailers, dollar stores and drugstores represented 9.3 percent of c-store traffic, according to NPD’s Convenience Store Monitor, which tracks the purchasing behavior of more than 51,000 U.S. c-store consumers. Meanwhile, overall c-store traffic decreased 2 percent during the same time period compared to 2010.

According to NPD, consumers shop at convenience stores due to their convenient location, long hours of operation and the ability to get in and out quickly -- often the same reasons for shopping at non-traditional convenience outlets. The percentage of customers who chose a c-store for one of these specific reasons is similar to the percentage who chose a non-traditional outlet for the same reason, NPD’s data shows.

Non-convenience stores' increasingly long hours are likely a factor in the growing competition, as well as these competing retailers’ ability to offer potentially better prices, selection, quality and value than c-stores.

"There is no doubt that convenience stores are facing stiff competition from non-traditional retail outlets," said David Portalatin, convenience store channel analyst for NPD. ""Convenience stores need to glean as much insight as they can from the preferences that consumers are exhibiting. When they do that, they can differentiate themselves from the competition by providing offerings most relevant to their consumers."