Sometimes I guess it's necessary to point out the obvious. Is it because society is getting more and more stupid? Probably yes. But that's no reason for the rest of us to be sarcastic about it. Take a look at these scenarios and decide for yourself it the sign was necessary.
We all read those studies on how most people can't even get through a couple of minutes without telling some kind of lie. To be honest that's fine, most of the time, but sometimes lying doesn't only get you into trouble. It's messing with someone else's feelings. I mean if you still got some pretzels don't tell me you're all out man. Take a look.
Do you know what petrichor is? It's the scent of rain on dry earth. Educate yourself. Learn the names of 11 things you know, but never knew what they were actually called.