What would you think if your employer did this...?

That's bullcrap. I don't know about your manager doing it out of "spite" but that's definetly not right. I can't stand when they wait until the last minute to hand out the schedule either-how do they expect someone to plan such things as appointments? We all have a life outside of work. My last job was a fast food place and they constantly were late. I think you should bring up your concern with the manager.