They probably have operated under presumptions that each cellphone owner/user or telco. customer is a stranger (i.e. resident) and perceiving telcos as an extension of the FCC's administrative law framework which they presume to be outside of the Constitution (a fallacy because the FCC is limited by the powers of its creator and so on). Corporate existence is also likely presumed. Also, in the U.S. cellphone companies are almost always a franchisee of at least one State of the United States if not a franchisee of the United States through some regulatory body.
My experience is that unless you make it clear to the contrary, they will presume in their own best interests.
Related terms:
administrative law, ultra vires, sedition by syntax, presumption, plenary power, territory, district, possess, Metro.