Not sure if this happens in smaller airports, but if the passport scanner is automated, they already take a picture of you.

they have a copy of a static image that they likely already have access to. very different to a high res alternate image, from a different angle, with a different expression, in different lighting

It's only static if they aren't using AI to analyze the tons of images they have of you from security cameras etc. Google Photos can learn and search for faces of a person based on one confirmed face a person. I'm sure Facebook can as well. There's no reason to believe the Government or TSA is or isn't doing this.

The ePassport gates in at the UK border both scan your passport and take a picture to confirm that it is indeed you. Since they already had my picture in the database from the passport I did not consider this an invasion of my privacy, and (for now) they are opt-in instead of opt-out.

Wait, what do they take a picture of, your passport or you?

You scan your passport, lean in for a picture of your face, and hand a receipt to a person on your way out.

Yes, except instead of a receipt the gate just opened and I went through.

Both.

It would make sense if that were true, but they already have his face. All he's really opting out of is them matching the one in their database when he's standing there. Maybe there's some value in that, but I agree the real value is not giving them your face to begin with and it's too late for that by the time you get to the gate... they've already got it.

There are already cameras everywhere though.