I think the person who came up with the word "weirdo" was actually one because who just sticks an "o" at the end of an adjective to describe someone?
Like I'm a white man, but I don't see people on the street saying "look at that white-o" or "did you see that man-o?"
Want to mess with your local grocery store? Buy a package of raw meat, cook it, put it back in the package, then return it and tell them it came out of the package that way.