Don't be eager to take offence. Don't be eager to take offence on behalf of other people.
Simon, I agree that we shouldn't be eager to take offence, but should the Jewish guests have waited a while and tried to figure out the motivation of the manager before being offended by the signs?
The woman may have indeed posted the signs innocently, not thinking how they would have been perceived, but we'll never truly know.
So, I will admit that neither I nor anyone can know what goes on in another's mind.
But we can have opinions about it.