We know there may be some privacy concerns regarding the use of our data but we don't allow anyone to systematically query our API to build phone number lists (We just allow 180 requests per min) We are very strict in the way people use our API. That's the reason we don't have an open registration process.

Yikes 180/m may seem like a lot ... but in the world of data that is a very small amount of usage. Your site says "big data" so this limitation begs the question -- Are you big data (enterprise) or not?

180/m? That's a database of over 10,000 records in an hour, and that's only if the querying party is stupid enough to not think of using multiple API keys in parallel.

This is already a business reality for most savvy organizations. Example, ordered pizza on saturday. Sunday, call another branch of the same pizza shop and the person answering the phone greets me by name before I even have a chance to say hello...

I was creeped out for a second, but then proceeded to order more pizza.

There's nothing weird going on there.. They took down your name when you called and they simply log you in their system with the phone # you called in with, your name, and likely your address if you got it delivered.

Information sharing is only recently the norm. Even between different branches of the same pizza chain.

I'm just saying it's not likely they used a API or something to find your name from your phone number. They are just using good ol manual registration to make your ordering time faster next time.