See this post at There I Fixed It.
I see this all the time. In fact, I get a $10 incentive bonus every time I report one. We call it a "straight connection."
I never thought of taking pix of these and submitting them to the above site, but now I might, because I've seen some real doozies. The one pictured there looks almost professional. I have seen them quite similar to that.
On the other hand, I once came across a straight connect that was made from a 50-foot garden hose. All the extra hose was just curled up around the meter box in the yard.
Sometimes they are attached by threading, as in the linked photo. Sometimes they get lazy and just attach them with hose clamps. This never works, by the way. Once I even saw one in which the hose was too small to fit over the pipe ends, so they just slit the hose ends a few inches and rammed them around the pipes, then screwed them down with hose clamps. Of course it leaked quite badly--if I may be allowed an understatement.
Most times, the water thief will use actual pipes to fit into the space where the meter should go, either PVC or galvanized. This usually works pretty well and if they have half a brain when they put it together, it won't leak.
The most ridiculous one I ever saw was when someone had used a radiator hose and hose clamps. Radiator hoses are not made to withstand that kind of pressure, and the middle part of the hose had swelled out to a diameter of about 6-7 inches and was just about ready to pop.
People always have a standard excuse when they see that I've caught them with a straight connection: "I'm doing a pressure test." Yeah, sure, whatever, dude. If your straight connect is still there when the investigator comes by to check it out in the next day or two, I still get my $10.
There is one other more surreptitious way to create a straight connect, and that is to break the register off the base of the meter so that the magnetic coupling is lost. Then you leave the register sitting there as if it were still attached. However, this only works up until the next time your meter is read. It is almost a certainty that the meter reader will, at the very least, reach in with his hook to knock some dirt off the display, and when he does, the broken register will fall off. He will also almost certainly notice that an unusually low amount of water has been consumed and will quickly discover the sabotage.
So, at best, you're going to run free water for a few weeks at the most before you are discovered.