I don't go around correcting people's writing here, but I definitely notice some of the oddities you mention. (I worked as a proofreader for many years, I just can't help but notice.)
I would add the misuse of the apostrophe to make a plural instead of a possessive. In plain language, for example, if you are serving a variety of vegetables it isn't written "vegetable's." Another common apostrophe misuse is "its" and "it's" - "it's" = "it is" - "It's possible." (It is possible.) But "its" with no apostrophe shows ownership - "Look at that dog, its tail is curly!"
I once saw a cover of the Oprah magazine with THREE fucked up apostrophes. I almost bought a copy so I could tear off the cover, edit it in red pen, and send it in with my resume asking for a copyediting job. XD
LOL
There's a guy, I think in England (?) who goes out at night and corrects apostrophes on signs. Adds them or removes them with paint. I'm not that kind of vigilante but it's tempting sometimes!
LOL!