Why can't under 18s who are EU citizens use automatic gates at European airports?

I heard from friend of mine who was travelling with her son to Los Angeles from London transiting through Amsterdam that she wanted to go outside the airport and take her son to see the city. Their transit time was 5 hours and the queue was extremely, extremely long. So she decided to go through the automatic gates which just scan the biometric chip in your passport, check your database for any crimes and let you through. She decided to let her son through first. When he tried it his it rejected him and an immigration agent came out to say that under 18s can’t use the service. I found this weird. Sure if they’re travelling on their own they might run away or get lost but why can’t they make it so that you prove that your travelling with an adult and then it lets you in?
They eventually decided to give up as the time would have taken too long. What are your thoughts on this?

Pure guess pulled out of my ass - to make child abduction ever so slightly more difficult? The immigration agent might need to check that it is appropriate for the adult to be taking care of the child.

Also there have been recent issues with radicalised youths running off to join ISIS.

The existing system requires no human intervention. The system just checks the DOB on the passport. I can’t think of a way to allow minors through without someone checking that a parent or guardian is accompanying them.

The arrangement I’ve usually seen is that if there is a group including children they just get shuffled to the side: there is always at least one lane that’s specifically set up for those groups, people who just can’t understand “place your feet on the silhouettes” and so forth, they go to that one.

At automatic boarding gates, the Nice Lady who hops over to assist because “I don’t know what’s the problem with this machine, it’s not letting us through!” just examines the passports oh-so-carefully and casually asks some questions of the children to determine if the group’s interactions appear normal. The group doesn’t get shuffled to a different lane unless it’s the quick one but they still get checked in a way a group of adults wouldn’t.

A little story about that kind of casual questions.

The answer is much more simple than that.

Egates can only be used in Europe by EU citizens. OP did not clarify if travellers were EU passport holders.

The egates system is quite complex. Ie the passport has to be held in a slot for a few minutes and then, if it is a 2 step gates process, the holder has to stand in front of the camera. It was decreed that only those who are adults can do these steps with minimal intervention by the operator. Get too many children doing this and the gates grind to a halt with all the instructions that have to be passed on. So for speedy movement of passengers only adults can use them.

But this rule has been relaxed in some UK airports where the age restriction has been lowered to 15.

And how is preventing said youths from using the automatic gates supposed to help? Do the border guards now ask all kids whether they’re running off to join ISIS, in hopes of catching those stupid enough to say yes?

The automatic gates require some kind of automated face recognition step, right? Face recognition for adults is far more of a solved problem than face recognition for children.

Well, they ARE running off to join ISIS, so maybe that’s not such an unrealistic strategy…

Youths ARE routinely stopped by border guards in the UK who are suspected of attempting to run off to Syria. I took a flight from London-Istanbhul last Easter and there were plain clothed police waiting to interview young men and women at the departure gate. They can stop people on a hunch, you know, they don’t need an ‘are you joining ISIS’ style question.

I don’t know the specifics of EU treatment of minors, but I do know that, when travelling internationally with my daughter, whether in/to Europe or between the US and Canada, there are all kinds of checks to make sure that everything is on the up and up.

They are worried about child abduction. Not so much the sex trafficking kind, but the divorce and custody dispute kind. And it gets complicated because my wife and I are citizens of different countries. It’s annoying enough when we’re all travelling together, but it’s especially difficult when I’m travelling with my daughter without my wife. It’s even more difficult for my wife, when she’s travelling with our daughter and not me, because my daughter has an American passport and my wife has a passport from another country.