While you do have a point about picking up extra work, you have to look at it in terms of maximizing your hourly averages. If you can make $80/hr average on a route by charging for attic work, etc., but only make $70/hr average by picking up an extra job, then the answer is simple, charge them. On the other hand, if you can pick up an extra job and that would raise your hourly average better than charging extras, then go for it. I've found that picking up extra work often involves greater amounts of downtime for such things as drive time, billing, etc., so there isn't much gained from picking up extra work, usually it just extends the total number of hours at your current hourly average.
This is CABL.com posting #207815. Tiny Link: cabl.co/m2d1