For me, understanding is the main goal. Grammar greatly aids this, especially when vocabulary is missing. If someone were to say, "where is the room with water?" it would be quick to understand that they mean bathroom. If someone were to say, "room is with water where?" it would be more tricky. In my opinion, I feel that people should keep grammar in mind and try to be grammatically accurate but it isn't the worst crime if they slip up. The main thing is to try.