Audience and writing

For college students, myself included, the primary focus of a paper is filling all the requirements a teacher wants. In the respect, many papers are dull, lifeless facts with little opinion and less real meaning. For instance, this blog, being my first, is probably going to be read as if I were talking to your face. So you are my audience. My writing is being effected by you because I don't know who you are. Because I don't know you I'm writing in a general format, with no real facts, just common knowledge stuff that I have gathered in my life and from my composition readings.
The simple fact is, I would never write this way for a professor. When a teacher is the primary audience, the paper generally contains five or more paragraphs, the first containing a lead, the subjects the paper will cover, and a thesis statement. Then it's fact, commentary, fact commentary; until the conclusion. So, that's one audience. For a big project that requires fliers, they need to be colorful, big print, friendly, and compel the audience to take part in whatever activity is being promoted.
The last paragraph is yet another example of the audience that is currently being written to: you. If I were speaking to you, I wouldn't organize my thoughts, I'd give you examples and jump from one topic to the next and then link them all together in the end. Good idea?
People like fluidity in most forms of writing, one topic to the next; that's easier to follow and understand. People often talk in circles, repeating their point over and over, each time adding something "new and exciting" to make said point seem more valid. In a paper there is a clear beginning and end. The audience that this is written for doesn't get an end. Endings don't make you think, they can be easily dismissed, and therefore render a paper meaningless.
That is why the audience is important. Meaningless papers need to be written sometimes; teachers, research projects, boring assignments whose only relevance is a grade. Papers with purpose are equally as important; asking people to donate blood, a resume , even a love letter. The papers that I enjoy the most, though, are those that don't necessarily need to stay on topic. Audience can give a paper life or make it devoid of value, that's how audience effects my writing.