Are you suggesting that passengers are required to be alert, undistracted, and focussed on safety procedures as they taxy out and take-off? Where does that rule come from? Let them relax, that's what they want to do.
No, thats not what was being suggested at all. Wader2 was, quite rightly, questioning how to go about dealing with an individual's decision to break laws and regulations stating electronic devices such as laptops, games consoles, PDAs, portable media devices and so on must be switched off for take off and landing, when the cabin crew aren't able to attend as it would risk their safety.
And whilst actually paying attention to the safety demonstration isn't required, there are plenty studies that conclude that those who pay attention for those 5 minutes have a greater chance of survival and are more likely to remain relatively calm in an emergency.