First the lmpg can be reset, look in the owners manual. There was one a car dealer posted on this web site last week with a very low one, he indicated he accidentally reset it, and had only driven the car through the car wash since resetting it.
Second, depending on where and how the car was driven could result in a low lmpg. I bought my 2001 cvt just over a year ago with 19k miles on it, the lmpg was 19 (look at my sig picture). After driving it for a while and checking how fast the lmpg was going up I was able to confirm that it had never been reset and that 19 mpg was what the car got over 19k miles. My worst tank was 59.75 mpg, and I had four tanks this summer over 77 mpg.
I believe that the first owner always had the climate control in auto (and therefore no autostop), I suspect he had a very short 2 or 3 mile drive to work every day (cold engine for whole drive), and he probably let the car idle in the winter to clear the snow and ice from the windows.
Don't let the low lmpg scare you off. Take it for a test drive and see what you can get with a 10 mile drive.
2001 Red CVT
19,351 miles lmpg 19.0 as of Oct 7, 2011
Best tank 78.9 MPG, 738.9 miles