I recently called a local steakhouse to be placed in their call-ahead seating cue and was told that the table should be ready in 30 minutes. When I arrived, I was told that it would be an additional 30 minute wait. I was not happy.
Nor were the others in the lobby full of people. While they tried to mitigate our hunger (and anger) by feeding us appetizer samples, it did little to improve the mood.
You may be amenable to someone playing a joke on you -- especially today -- but having a restaurant provide a seating time that was a joke wasn't funny.
I have said before that the cardinal rule of service is to align expectations with reality. If the wait is an hour, people are much more agreeable to it than saying a half hour and meaning an hour. If you say it is April Fool's Day, people are much more receptive to being pranked than on other days.
You've got a free pass for exaggeration today...but it expires at midnight!