I guarantee the proprietor will be complaining as soon as you have left. If the place was busy and you were occupying a table without ordering anything, maybe.

I guarantee the proprietor will be complaining as soon as you have left. If the place was busy and you were occupying a table without ordering anything, maybe. But if the place was otherwise fairly empty, they probably don't mind very much. It can even be a benefit to have a few tables occupied so that the place doesn't look completely dead.