Improper use of the apostrophe for plurals bugs the hell out of me. Except in narrow circumstances, one places an apostrophe before an s to denote possession. If one is discussing more than one of something, the apostrophe goes after the s. One does not place an apostrophe before the s to simply denote plurals.
No apostrophe is used in the following possessive pronouns and adjectives: yours, his, hers, ours, its, theirs, and whose. (Many people wrongly use it’s for the possessive of it, but authorities are unanimous that it’s can only be a contraction of it is or it has.) Except for one’s, no possessive determiner has an apostrophe. A number of them, like its, are homophonous with pronoun-auxiliary contractions. As was previously noted, the pronoun its is very commonly misspelled; not only is there the homophone it’s (it is or it has), but ‘s is a genitive clitic.
For cryin’ out loud people, get it right.
Random Thoughts on Everything and Nothing 
That bug’s me too 😉
This subject has become almost taboo in Britain. If someone complains at its inappropriate use they are denigrated. There are even moves afoot to dispense with its use all together. The authorities seem to think that as long as people can work out what you mean – well that will do. The same goes for spelling too. Is it any wonder that we’re called UK now, and no longer GB?
Oh cripes – I’m getting serious. Can’t have that can we!
AMEN!! Amen amen amen!! I’ve always just bristled about this, but it’s getting worse and worse. 90% of the known world seems to think that if you put an “s” at the end of anything, it must be preceded by an apostrophe. I even saw it on the back of a truck today…”if you can’t see my mirror’s, I can’t see you.” Aaaaaaargh! For cryin’ out loud, INDEED.