dcpatti

When you book for other people you do have the option of adding in their email address, not just for sending the itinerary but for notifications (change in schedule etc). I would not be surprised to see US culling these reservations for email addresses without a DM number; any smart airline would do that, because the more people signed up for the frequent flyer program, the more valuable it becomes. Your FF program is worth more if it has more members (analysts have been saying for a long time that UA's MP program is the most valuable asset, even moreso than planes). You can also charge your advertisers more if you have more people on your mailing list.

You can always see if the email is legit by taking the confirmation code and date of travel on the reservation and running it through the Manage My Reservations tool on US website. If it comes up and it's in your name then the airline got your address from whoever booked the reservation.

FWIW I think the whole "myusairways.com" domain is a throwback to the days when *everyone* had a MyWherever.com domain. It was supposed to be more cozy and personal for non-technical users for some reason. Not that there'd be different content, just that including "my" in a domain name is somehow supposed to make the customer feel cozier. Maybe they're not changing it because they don't want their mails going to peoples' spam folders when the customer doesn't update their Trusted Senders list.