Technically, any place that derives a majority of its revenue from alcohol is prohibited. That makes it pretty difficult since alcohol is pretty abundant, especially in the areas where concealed carry is most wanted.

I will also say that most people seem oblivious though.

@scotchymcdrinkerbean  may be able to provide better info on the convention center.

If it is a restaurant, you are good to CC (though somewhat stupidly not OC,) even if they also sell alcohol, thoughit is not legal in the bar area of said restaurant.  As for how to tell the difference between bar and restaurant, common sense should cover you---a big bar across the length of the establishment but a couple booths to eat at?  Yeah, should you be discovered you are not really gonna be able to argue you thought it was a restaurant.  As for an actual restaurant with a bar area, if it is small and unobtrusive, a good rule of thumb is to see if you can view any video poker machines---if you can see one openly, you are almost certainly in a bar.

As for the convention center---news to me.  They are not posted that I know of, and they do not fall under any of the prohibited places in the law.  And they do not bar off duty LE from carrying (though if they did, it would not violate LEOSA.)
If they ain't posted, carry there is legal.  Mind you, some events may have a no weapons policy for their part of the building, but they're gonna have to post that fact, and would most likely have metal detectors and security.

You can't enforce a non-published, non-posted policy.