How many other people does an average Starbucks visitor interact with?

Now consider the same for Facebook.

Every starbucks is a different place. If there was a single building 50 million people freely walked into every day, I'd say that should be considered a public place.

You might want to read up on Starbucks "Third Place" policy.. They actually DO want to be a public place.

"In the mid 90s Starbucks incorporated this philosophy into its retail design and business strategy: “We want our stores to be the third place' "

https://www.mjvinnovation.com/blog/third-place-and-the-starb...