Oops.
I encountered this abomination in a motel in Bentonville, Arkansas. Lest you try to foist the blame on the Arkansas education system, Wyndham Hotel Group is headquartered in Parsippany, NJ, across the Hudson from NYC.
I blame Bill Gates. The geniuses at Microsoft have yet to come up with a solution for this egregious error; never mind that they’ve had three decades to do it. But some folks seem to believe it is OK. After all, Microsoft Word and other word processing software automatically “correct” it. (They have dubbed it “smart quotes.”) Ergo, it must be correct if Gates and MS Word and their counterparts say it is.
Sigh.
What’s the problem, you may ask? The “ ‘em” word. I see this frequently in manuscripts I edit. The punctuation mark preceding em should be an apostrophe — “ ’em” — not a single quotation mark. They are not the same; they have distinctly different shapes and functions.
An apostrophe (looks like the “close quote,” not the “open quote”) indicates missing characters, in this instance the “th” in them, but more commonly in contractions, such as “you’ve” (you have).
However, a quotation mark, whether single or double, signals to the reader the beginning of a quotation and requires its partner mark at the end of the quotation; e.g., ‘em.’
Note the correct usage of the apostrophe in the companion cup: “you’ve” — I love the irony.
However, the so-called smart quotes will not allow an apostrophe to follow a space, even when that space precedes a truncated word. So, smart quotes reverses the mark, turning it into a single quotation mark.
What’s the solution for you victims of unintended consequences?
See: Ten Most Common Errors Made by Writers — #2: Apostrophic Calamity: Apostrophe vs. Dumb Quotes
Polishing Your Prose 
My solution is to type the word as it should be (“them” in the case of the coffee cup) then add the apostrophe and delete the letters it represents.
Or I turn off smart quotes.
That’s a good’n.
Exactly what I was going to type! You have to fool the software with a sneaky end-around–which then completely sidetracks the momentum you’ve built up toward your Coffee Cup Pulitzer. Otherwise, if you can’t beat th’em, join th’em!
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