What the time table will show is presumably the great circle distance between the airports. (BTW, there are plenty of free airport distance calculators on the web that will also show you the heading and a map with the great circle route.) In reality, you will likely fly a little further than that due to directional constraints for take-off and landing and the pilot might deviate from the great circle course for jet stream reasons. Will UA keep track of that and give you the extra credit you deserve? Somehow I doubt that.