Need to vent

While I was at work the other day my manager pretty much ignored me and didn't say anything to me and didn't even bother to even say hi and told someone else tell me i could go home because it was slow. I'm just like you can't even come tell me yourself that I can go home? They don't have to like me or have an hour long conversation with me but they can't take the time to just say hi? It takes a second to say that. They're managers and they are supposed to be in charge of people. If you can't even say hi and just act friendly towards your employees then you aren't a good manager All my coworkers were upset about it too