Earlier quoted context omitted.
> It makes me wonder if it might be useful, as a public service, to have some kind of free business listing that (with your permission) automatically duplicates what you put on Facebook, just to encourage people to at least be discoverable outside that walled garden. You know that Facebook would immediately start either offering incentives to keep all your data in the walled garden, or spreading FUD about the duplica…
They can also remove that integration any moment they like, by revoking an app ID. Very likely they'll be able to find a paragraph in their developer program T&C they can claim was violated by GP.
It's funny (in a sad way) but even for my friends who own restaurants, where I'd be more than happy to give them free hosting or help them upload stuff or whatever, they don't see anything other than FB as worth the effort even to just keep track of.
Obviously that's not universally true, plenty of places (especially higher-end ones, and ones with significant delivery business) have dedicated web sites that are kept up to date.