The title implies (well, I'd say explicitly states with the word "vetting") that restaurants are trying to filter guests, maybe to avoid troublesome ones with uncouth posts online or something. And many of the comments are replying to that interpretation, based on the unfairness suggested in the title. It's not only clickbait, it's outrage bait, designed to spark anger.

The article itself is about how restaurants have gone above and beyond for some guests where they've been able to tell from their social media that they're celebrating a special occasion or some other thing like that. To make the guests' experience better and memorable.

There's a privacy angle to this, should restaurants do that, slippery slope, etc etc... but many of the comments aren't talking about that. They're responding to the inflammatory title.

I don't think we often get such a clear picture into the why behind online outrage and how clearly manufactured it can often be. I think it's easy to believe people are angry for a good reason, to take the anger "on good faith" in some sense. In this case, with the title being so far from the article, it's clear to see what's going on. And makes one wonder about the rest of the outrage out there.