Personally, I've seen as many photo driving licences as passports in the CTA channel.
Don't know/care what airlines do with boarding cards TBH and it's up to the Rozzers how many officers they choose to place in the channel rather than the airport. Sometimes they attend and sometimes they don't. Depends what's on Sky Sports I suppose.
(That was a joke before anyone get's their knickers knotted and rants about taxpayers, value for money, expenses, pensions, no-one getting sacked in the public sector when everyone else in the private sector is because everyone in the know knows the cops only have Setanta Sport in their office)