I have something that's been bothering me for while. I used to not care, but suddenly I developed a new grammar twitch that hasn't gone away. It drives me up the wall when people misuse 'quote' and 'quotation'. Here's the difference:
--QUOTE: a verb, TO QUOTE. "He quotes random movie lines constantly."
--QUOTATION: a noun. "He loves movie quotations."
I suppose some of the confusion enters in from a lot of words that are both nouns and verbs. (Example: DRINK. He drinks. He takes a drink.) Also, you can call in for "a quote" on some service (an estimate, if you will)--call in for an insurance quote! So really, it's no wonder that people just use "quote" when they mean the noun "quotation". I really shouldn't get all bent out of shape on it.
But none of us can truly know why the gods decide which things will drive us crazy. And right now, those that misuse quote-quotation are on that list.