As ive said before... its just introduction by stealth. The aviation industry is a rather paranoid world and in the public eye its deemed very sensetive.
The government knows these things are deadly unpopular so there just exploiting this issue and all things connected with it to "get their foot in the door" if you will. Really really simple yet effective tactics.
Once these are compulsary for airside staff there slightly embeded into society meaning other people are more likley to accept them! There usless pieces of plastic trash ... expensive ones that i might add everyone is going to have to pay for in some respect. Nothing gets replaced, nothing gets more secure nothing changes aside from the fact your monitored. WHY? Its just another control mechanism the same as the 3 million odd security cameras in operation in this country. The government is trying to provide the illusion that these things (like CCTV) make you more secure. Ok CCTV cams do prevent crime and are a deterant but theres still too damn many of the things! The argument for ID cards is 10 times less plausable!
All these things are, are cattle brands nothing more nothing less and airside workers should not be the guniea pigs for the slow introduction of these things into our lives its just well and truley bent! Even they can't properly justify them!