That kind of thing goes on in the US too. A lot of the insane right-wing comments you see on the bottom of news stories are actually by paid corporate shills funded by shadowy backers. If your political opinions are genuinely and honestly right-wing or left-wing and you happen to be a writer, I don't see anything wrong with accepting payment to advocate for the things you already believe in. If someone wants to pay you to express your opinions, whether right-wing or left-wing, you get the opportunity to make a living while also working for the causes you believe in. That's a win-win situation.
On the other hand, if your actual political opinions are different from what you're being paid to say, or if you are actually politically apathetic but are willing to rant fanatically on some news story if the money is right, then this is not an honorable way for a writer to make a living. Being a paid political blogger is not wrong, but being a paid political liar really is. In writing for a living as in everything else, there are ethical standards we must all do our best to live up to. I wouldn't write a political essay I didn't agree with no matter what I was offered- some things are just more important than money.