Language is not a one way street. Being able to manipulate another person's actions and words through speech is as much a part of language understanding as being in a position to have others manipulate your actions and words.
Part of knowing a language therefore is being able to speak and write it. In order to learn how to speak and write it, you are not going to get away without speaking and writing it.
And even if Krashen's hypothesis that input is ultimately the whole story were true (which by definition it isn't), production would still play a critical role in memorization. Every time you struggle to find a word and eventually conjure it, it gets reinforced.
I honestly don't get how people talk in noisy bars and restaurants. I struggle even in English. One almost has to shout in the other person's ear. If it's that close I am thinking more about how my breath smells after having a few drinks rather than topic of discussion - lol.