A drug dealer provides a service. If a dealer were to decide that he didn't want to sell to you, and you then proceeded to take the drugs, that could be construed as theft of services in the same context as the judge here. Or perhaps someone was going to set up a growing operation for you and was then going to back out. Or someone said they could rig you up free cable, or something. Regardless, in all those cases, the services provided are illegal and the person who was "ripped" off wouldn't have a leg to stand on.