Of course it's a thing. Have you not heard anything about the FDA regulations which went into effect about age verification? (And the place being located in CA only makes things worse.)
Their site policy is posted right there:
http://www.tastyvapor.us/age-verification/
If your info provided for the purchase transaction isn't automatically matching your info in public records data for some reason then they would be asking for a copy of a photo id for age verification.
Not legally.... doesn't mean they won't require a match though.. CYA and all......Does it need to have my current shipping address?