I'm also seeing this in my environment, which has cross_az_attach=False.

Nova AZ:
root@cantu-rpco-master01-utility-container-e592a0d6:~# nova availability-zone-list
+----------------------------------------------------------+----------------------------------------+
| Name                                                     | Status                                 |
+----------------------------------------------------------+----------------------------------------+
| internal                                                 | available                              |
| |- cantu-rpco-master01-nova-cert-container-0af67b8a      |                                        |
| | |- nova-cert                                           | enabled :-) 2017-04-19T16:54:00.000000 |
| |- cantu-rpco-master01-nova-conductor-container-2fabdc9a |                                        |
| | |- nova-conductor                                      | enabled :-) 2017-04-19T16:53:57.000000 |
| |- cantu-rpco-master01-nova-console-container-7e2e9044   |                                        |
| | |- nova-consoleauth                                    | enabled :-) 2017-04-19T16:54:00.000000 |
| |- cantu-rpco-master01-nova-scheduler-container-62144ac1 |                                        |
| | |- nova-scheduler                                      | enabled :-) 2017-04-19T16:53:56.000000 |
| alex                                                     | available                              |
| |- cantu-rpco-master01                                   |                                        |
| | |- nova-compute                                        | enabled :-) 2017-04-19T16:53:57.000000 |
+----------------------------------------------------------+----------------------------------------+

Cinder AZ:
root@cantu-rpco-master01-utility-container-e592a0d6:~# cinder availability-zone-list
+------+-----------+
| Name | Status    |
+------+-----------+
| alex | available |
+------+-----------+


Created bootable volume:
root@cantu-rpco-master01-utility-container-e592a0d6:~# openstack volume create --image $IMAGE --availability-zone alex --size 2 boot_vol_alex
WARNING: openstackclient.common.utils is deprecated and will be removed after Jun 2017. Please use osc_lib.utils
+---------------------+--------------------------------------+
| Field               | Value                                |
+---------------------+--------------------------------------+
| attachments         | []                                   |
| availability_zone   | alex                                 |
| bootable            | false                                |
| consistencygroup_id | None                                 |
| created_at          | 2017-04-19T16:52:31.729774           |
| description         | None                                 |
| encrypted           | False                                |
| id                  | 9ee8b04e-edc4-4d70-9842-2d0781d414f9 |
| migration_status    | None                                 |
| multiattach         | False                                |
| name                | boot_vol_alex                        |
| properties          |                                      |
| replication_status  | disabled                             |
| size                | 2                                    |
| snapshot_id         | None                                 |
| source_volid        | None                                 |
| status              | creating                             |
| type                | None                                 |
| updated_at          | None                                 |
| user_id             | d0d694e2a7624a618c749ce117751e28     |
+---------------------+--------------------------------------+

Attempted to create instance from bootable volume:
root@cantu-rpco-master01-utility-container-e592a0d6:~# openstack server create --volume boot_vol_alex --flavor $FLAVOR --nic net-id=b35ac608-2c01-45d6-86de-5d12304279ff --availability-zone alex alex_boot2 
WARNING: openstackclient.common.utils is deprecated and will be removed after Jun 2017. Please use osc_lib.utils
Block Device Mapping is Invalid: failed to get volume 9ee8b04e-edc4-4d70-9842-2d0781d414f9. (HTTP 400) (Request-ID: req-f76e65f2-4a72-4184-ba36-e9fdca5bbad0)
root@cantu-rpco-master01-utility-container-e592a0d6:~# cinder availability-zone-list