I think this and this answer of mine should more or less answer your question. The short version is that everyone spoke Vulgar Latin. Vulgar Latin isn't a monolithic block, it's simply the colloquial form of speech and varies greatly depending on location, period, and social status. "Classical" Latin is a purely literary invention--in much the same way that we don't speak the way we write journal articles, no Latin speaker would speak the affected literary style of writing and oratory. That's not to say that the educated didn't have better Latin--an Oxford don doesn't speak the same way as a construction worker, by and large. But that same Oxford don doesn't speak as if he's writing a journal article either