Devon & Cornwall Police to use metal detecting arches?

Devon & Cornwall Police have announced that they intend to install these arches on the streets of towns and cities. While it may be a good idea to detect weapons what about the innocent people who will be forever turfing out their pockets and handbags, won't they soon become frustrated with the whole thing. I feel it's just an extension of the suss laws and is going further towards a Big Brother state.