I am in the process of grading ~50 midterm examinations from my Public Speaking class. I have encountered several instances of misplaced quotation marks (as well as other writing errors and general incoherencies) and avoided the impulse to mark off points for such things. But I did appreciate the student who said the speaker in the sample speech might change the "wording" if she were speaking to Congress.
I don't usually post the following: newspaper headlines, personal email, craigslist postings, unprofessional websites. I also tend to not crosspost things from other blogs, since I have so much unique material waiting for me to get to it.
Things I see a lot: silica gel "do not eat"; hair dryer labels; inside the bus "do not drill"; Wal-mart sign about IDs; coffee machine with "2" cup sizes; employees must "wash hands".