What is the "U.S. point of contact" in the ESTA application used for?

Question

Last year I went to a meeting on the east coast of USA. I applied for an ESTA, and when the application form asked for a "U.S. point of contact" I put down the work address and phone number I had for the meeting organizer.

Now I'm going to the west coast for a different meeting. My ESTA is still valid, but there's no way to update the point-of-contact information.

It is quite well known that I don't need to update this information. I don't doubt this. (At least I very much hope they're not going to call the guy who organized a meeting in Boston last year if there's a problem with my entry at San Fransisco next month ...)

But I'm curious: Why do they ask for this information in the first place, when it will predictably be out of date for many arriving travelers? Is there any official word on what this is for?

[Note that this is a different field in the application than "address while in the U.S." which I can change for a subsequent trip].

Answer 1

Presumably the same reason as on the other forms, like the DS-160:

Your U.S. Point of Contact can be any individual in the U.S. who knows you and can verify, if necessary, your identity.

They also request the relationship you have, if any, to the person.

From my own assumptions, this would be to also check your reason for visiting - if your point of contact is say, a girlfriend, they might just double check your reasons for coming (are you trying to stay/work?).

Answer 2

According to the ESTA frequently asked questions:

Why is it necessary to expand the amount of ESTA information being collected from VWP travelers?

Since 9/11, the Visa Waiver Program (VWP) has evolved from a travel facilitation program concerned about the threat of economic migration to one with more robust security standards that are designed to prevent terrorists and other criminal actors from exploiting the Program.
...
DHS must be agile and vigilant in continually adapting to evolving threats and hazards. DHS has not made a significant upgrade to the ESTA application in the six years that the system has been in operation, despite a significant evolution in the terrorist and criminal threats to the United States. DHS has determined that the additional data fields to the ESTA application will enhance DHS's ability to screen and more accurately and effectively identify travelers who pose a potential security risk to the homeland.

So the official explanation is that it helps the US fight against terrorism. However I presume the actual explanation is the need for a security theater, rather than any valid concerns. Don't look for any real rationale as there isn't one - it's simply an example of bureaucracy collecting information for the sake of collecting it.