Our family has a dumpster diver. My sister-in-law enjoys the fun of going to other neighborhoods, especially ones more affluent than her own, and getting free stuff. Now, the key is that the people do not know she is taking their stuff. Instead they put it out for the garbage company, and it disappears. Every time we visit my sister-in-law and her family, she has something else to show us that she found in the trash.
While we find it odd, I did not realize until recently that there are many people like my sister-in-law who consider dumpster diving a serious hobby. These people actually think about dumpster diving often and believe that there is an art to successful diving. My sister-in-law told us that she picked her car because of its usefulness for dumpster diving. It blends but has plenty of cargo room for the goodies she will be getting. I was appalled, but after doing some basic research on dumpster diving, I found that it can be a viable hobby and that there are even codes of ethics, so to speak, in dumpster diving.
First, dumpster divers, at least the serious ones, believe very strongly in obeying the laws. They will not violate dumpsters marked with no trespassing signs, and they always make sure that dumpster diving is legal in the places where they plan to go. Now, that may not seem like such a big deal, but there are few hobbies where people are encouraged to educate themselves about the laws before partaking. The main reason that dumpster divers do not want others participating in their hobby illegally is because it is embarrassing for many to get caught. Plus most people believe that should others violated posted signs and such, then dumpster diving could be off-limits for everyone with a public outcry.
Second, dumpster divers do not want to leave a mess behind. They simply swoop in and get what they want. If they see nothing, they move on. These divers do not stay around. They believe in quick entrances and exits. They also will pick up anything they put on the ground while dumpster diving so that they do not alert anyone to their presence. Plus, it is just generally good etiquette not to leave trash (literally in this case) behind when you leave.
If you want to try dumpster diving, my sister-in-law and others like her warn that you will have to abandon any inhibitions you may have. You should start by spending a few nights (or even weeks) going to places that you think may be good. Go into upper middle-class neighborhoods that do not seem to have too many rules. Otherwise, you may risk someone calling the cops. Scope out the trash left on the curb for a few nights. If you still live in a place with large dumpster areas, then do drive-bys every night for a week or so to see if you can eyeball anything good.
Then you should just do it. The reason that you want to scope first is that the fun of dumpster diving, I have been told, is in finding something awesome in the trash. Once you have a great find, you will be less worried about getting caught because you will be thrilled with your new acquisition. Spending your first night going through trash without finding anything will not be any fun. In fact, you may go home discouraged and even a little embarrassed. Instead make sure you are picking good spots so that you will be more likely to find something.
As long as you are certain that what you are doing is legal, then you should be okay. If anyone comes out and asks you to leave, then you should go. Do not try to argue with the person because you probably are still on private property (or close enough that someone with a big mouth could convince the cops to bust you anyway). Walk away when asked and avoid that house in the future.
Though I find the idea of dumpster diving appalling, it apparently is something that others enjoy. The idea of getting something cool for free is too much to pass up for people who are always thinking of the next great bargain.