Yeah, the lunchtime ride thing is a huge part of it. 50-some miles of somewhat urban, totally non-scenic riding that I've done a bazillion times, all by myself, on a road with a 65 mph speed limit, or 25 miles with a bunch of friends on scenic quiet roads.
If I lived 5-15 miles from work I'd ride in a whole lot more often, especially if I lived in the Boulder area and had a pretty ride in, with coworkers who commute in every day. But a solo ride on busy roads is demotivational.