This is why it should be possible for theatres and the like to set up alternate base stations that cell phones connect to, this way 911 calls and text messages incoming may still be delivered but no incoming/outgoing calls may be connected.
In the scenario I'm describing, the doctor is going to the theater when they get a call from the hospital saying there's someone there who needs their skill. (It's actually in their contract that, while they're on-call, they have to remain within a certain amount of travel time from the hospital so they can get there in time. This does affect home purchases.) If their cell phone is blocked, the call is missed and someone may very well die.
You could (presumably) attempt to fix this with technology. It might even work for a while, but when it breaks, someone could very easily die. And they'd have died of someone else's dislike for cell phones, which is not a good reason.
