@Scott2157 Yes, it's allowed. The host is protecting his property, and it's his right to ask.
You must realize that for every honest, trouble-free guest, there are those with unfinished profiles, fake names, no photo in their profile, and other issues. AirBnB does very little to vet guests, as well as very little to support hosts when trouble arises from a guest.
It's also a security issue, and may be a matter of simply ensuring that the person who booked is also showing up for the reservation. Third party bookings are not allowed on AirBnB.
If I were to ask the same, and the guest refused to comply, I would not allow the stay. You shouldn't take it personally.