If a company or individual posting to craigslist is having trouble with competitors, fake posts, harassment, etc., there are a number of ways to get things done. I'm sure that Craigslist, like every other site, makes people jump over a few hurdles before they can get in touch with a live human.
Calories Burned. On average, a 150-pound person burns 91 calories biking for 20 minutes at a leisurely pace of less than 10 miles per hour, according to the Calorie Control Council's Get Moving Calculator. The caloric burn increases to 136 calories when intensity escalates to a moderate pace, 12 to 13.9 miles per hour.
However, my bike rides would have me doing 2 miles in 15 minutes, whilst I covered 1 mile in 20 mins when walking. So, I could walk for an hour and burn 300 calories, or I could cycle for an hour and burn 272 calories. Not all that much different, at that level.