Sure, but I'm not inclined to believe that number on its own. Practically, even the cheapest grocer like Aldi could turn out to be expensive than the quoted $3.37.
Rice and beans - been my staple for most of my life - isn't too much more than this. Two cup dried rice + two can beans is around $4 and that is generally enough for me. Although it is much better with a few eggs and some hot sauce or salsa as well.