Historically, pen/trap is much less controversial than the "Room 641A" crap, so even if the legal department examines every request (which isn't true for every telco), nobody fights any of them. This was actually the source of the unfortunate "if the phone company knows who you call it isn't personal information" theory. Each telco treats this as just another line of business, and they send invoices to law enforcement agencies. "Modern" switches are smart enough to track called and calling numbers without the installation of actual old-fashioned "devices", so I wouldn't be surprised to learn that the price of this service has decreased. However, this is such common knowledge in telcos that I'd be shocked to find it isn't common knowledge in courthouses. So, the judge is either ignorant or dishonest.