Your credibility was completely lost when you typed menu's.
Given the general high quality writing of the post, I think Immerman knows full well that plurals don't usually require apostrophes.
I'm guessing that you are not aware of the usage where certain words ending in vowels have an added apostrophe to emphasise that the "s" isn't part of the root word.
It's rarely used for words these days, but is still common for symbols and non-word constructions ("count the &'s", "mind your P's and Q's").
As an example of why this can still be very useful for words, though: there are two pages on Wikipedia about people named "Peni".
How would you refer to both of them as a group?