Originally Posted by
cauchy
The expense isn't unnecessary - conducting immigration checks to prevent unlawful immigration, stop people from working without the right visa (thereby protecting UK jobs), and providing a deterrent is perfectly justifiable. Illegal immigration isn't so easy to detect with an eGate, and the Gate can't provide the deterrent of "you'll have to explain yourself to an officer".
I’m not sure I follow your argument. The egates are actually manned - an officer sees all the information they would see at a booth except they see it for (depending on country) somewhere between 5 and 10 of the gates. If they spot something dodgy the message will be exactly the one you say they can’t: the gate won’t open and it will say please go and see an officer and there is a queue specifically for that.
Conversely, if you go to a manned desk, many will simply swipe your passport and give it back without any other exchange than hello and thank you.