[eduction]

I believe Google's data is now based largely on restaurants updating Google directly with that info. You can see in some searches where there is a prompt for the business owner to register and update/correct the hours. In my neighborhood it's to the point where many won't even post hours on their website any more, you have to check Google, which is annoying as I try to use other search engines. Sometimes on Google I'll see "updated by business owner 12 days ago" or similar. I presume Yelp has a similar (but probably smaller) database of its own.

In any case the impact for LLMs is the same, it's unavailable to them (unless they are being developed inside Google!).

This seems like a specific area where a "Semantic Web" solution could work well - some HTML tags that are specific to hours of operation, which business owners would embed in their website.

UPDATE: It looks like there is some prior art on this idea, I am not sure how widely this is supported https://schema.org/openingHours