Amazing. I have to see that documentary. Do you score every time?
There is almost always something, unless you show up right after they garbage truck comes. The haul pictured is somewhere between average and really good. If the store closes for a holiday, the day before is often really good, since they have to throw out everything that "expires" for two days instead of just one.
When my wife was going every day (Pre - broken collar bone and pregnancy) we would go 6 to 8 months without buying milk, eggs, spinach, bananas, apples, yogurt, strawberries. We would stock up on things like ground beef, tortillas, cheese, lunch meat whenever we found them since they were not as frequent.
In addition, we have occasionally found open bags of cat litter and dog/cat food at the pet store.
If there was ever a really large amount of something and we couldn't figure out why it was thrown out (not expired or damaged) we would check for recalls. It's been about two years and we haven't gotten sick from anything we've dumpstered. For a while our under-two son would ask for bananas every time he saw a dumpster. :D