Truly, I'm not a pedant.
I can proof-read with reasonable accuracy, and I am aware how punctuation is supposed to be used. I understand the differences between there/their/they're, and your/yore/you're... I hope I use them correctly, too. But anybody can make a typing error. I'm responsible for what I type (and glad when people mention mistakes I might have made) but it's not up to me to judge or criticise anybody else's use of language, unless they've actually asked me to check or proof-read something. Even then, I hope I would remain placid and friendly about it.
Incorrect use of grammar or spelling just isn't that big a deal, as far as I'm concerned. If it becomes impossible to understand something, it may be a problem, but we're all different, and - to me - the content is far more important than its fine detail. I suppose I would be annoyed if I read a published book that was full of proofing errors - it shows lack of care for the reader - but in general, on occasion, I mentally shrug and move on. Life is worth more than a few spelling errors.
Likewise, while I sometimes find classic greengrocer-style apostrophe errors mildly amusing, they don't cause me intense anger and frustration. However, if you are the kind of person whose blood pressure rises dangerously when you see such things, please read no further.
Out of all the incorrectly-used apostrophes I have ever seen in my life, this one - which appears twice on this large poster in a big supermarket not far away - is probably the oddest: