Lawrence Lessig in his book Free Culture talks about the effect of all-rights-reserved copyright on news broadcasts:
We take it for granted that we can go back to see what we remember
reading. Think about newspapers. If you wanted to study the reaction
of your hometown newspaper to the race riots in Watts in 1965,
or to Bull Connor’s water cannon in 1963, you could go to your public
library and look at the newspapers. Those papers probably exist on
microfiche. If you’re lucky, they exist in paper, too. Either way, you
are free, using a library, to go back and remember—not just what it is
convenient to remember, but remember something close to the truth.
Television, it turns out, is even more
ephemeral than the Internet.While much of twentieth-century culture
was constructed through television, only a tiny proportion of that culture
is available for anyone to see today. Three hours of news are recorded
each evening by Vanderbilt University—thanks to a specific
exemption in the copyright law. That content is indexed, and is available
to scholars for a very low fee. “But other than that, [television] is almost
unavailable,” Kahle told me. “If you were Barbara Walters you could get
access to [the archives], but if you are just a graduate student?”
The same is generally true about television. Television broadcasts
were originally not copyrighted—there was no way to capture the
broadcasts, so there was no fear of “theft.” But as technology enabled
capturing, broadcasters relied increasingly upon the law. The law required
they make a copy of each broadcast for the work to be “copyrighted.”
But those copies were simply kept by the broadcasters. No
library had any right to them; the government didn’t demand them.
The content of this part of American culture is practically invisible to
anyone who would look. (p109-111)
When you say "After all news get old after a few hours, nobody is interested in them anymore" that is a very short-sighted perspective. Often we don't know what will be significant in later decades and centuries. The first local campaign speech of a future Prime Minister or President may well have been broadcast, but if the rights holders restrict its archiving then in thirty years' time it may be impossible to find and view.
And that's for news items that eventually turn out to be significant. There are so many more broadcasts that will be important, not for the events they show, but as a window into life in a particular place at a particular time. In 100 years time how many of the interviews with regular American citizens talking about the Ferguson unrest will still be accessible?
We'll never be able to archive everything, but we have the technology to archive a lot. We don't know what our grandchildren will want to rewatch, so we should try to archive as much as we can. Commercial broadcasters may never allow that, but we should at least demand from our public broadcasters the freedom to archive their new broadcasts.