I don't know how stupid you think I am, hm, but apparently my IQ barely seems to rate above room temperature in your eyes. I know how the plural possessive is formed. I also know the apostrophe isn't dangling
; I just called it that because I wanted to. It seemed very apropos to me because that's what it looks like to me: an apostrophe dangling above a period. Is everything 100 percent formal and serious 100 percent of the time with you? Do you never veer from the straight and narrow when it comes to language? Gee, how exciting life must be that way.
As far as wrong, right, and common goes, all I can say is I read a lot, every day, and all sorts of people's writings. I do it for a living, and I am simply reporting my observations, and they are that, in this case, the apostrophe is more often missing than not. As to why it's missing: I was merely taking a guess. Who knows what the real reason is. I don't.
Once again, maybe I should have just overloaded my previous posts with smileys to make myself better understood. It's moments like this when I just want to stay away from this forum for good.