Is there any good reason to be aware of the mainstream media?

On the whole it is certainly best to avoid the mainstream media; because - except in very small and short doses - we will soon find ourselves interacting with it; and then, at the detailed level of specific assertion, we will be interacting with zero informational content. 

The main reason I can think of, to be aware of the mainstream media, is simply to recognize how opposed or unrelated it is to reality at a thematic level; and to keep in mind this fact. 

And for this; a swift glance at the Headlines is sufficient. 

After all, from the media POV - the Headlines are (apart from fake-images) the only thing that really matters.