More than once I've heard variations on "What use is there in teaching people how to go to the store and buy milk?" as a response to conversational/active/living approaches to classical languages. There's a grain of truth in there, yes: one is unlikely to go down to the local store and buy some viands in Latin. But I now have a standard rejoinder to offer up, "How can you meaninfully say that you know a language, when you couldn't go to they shop and buy some milk?"
If you can translate Cicero but can't buy milk, latine, there's a problem.
You're doing it wrong.