I had your reaction. Trust me on this, it works. I would tell you to like BCC so that I can spam you to prove it, but I took off my like buttons right after figuring it out. I thought it was a huge violation of my users' expectations, which I had been explaining as "Like this and your friends on Facebook will see it."

I can confirm too. A few months ago when Facebook pushed to convert everybody's "likes & interests" into "Like <page>" things, I initially agreed to it, to see what happened. What started happening was that my News Feed began to fill up with spammy events/messages being pushed out from all the things I Like-d. Bands, movies, books, TV shows, etc. The problem was it became much harder to see "real" events/activities from the people I was connected to, friends and coworkers, etc. So I went in and de-Liked all of it.

Make a bookmarklet with this code:

  javascript:(function(){try{var%20url=encodeURIComponent(location.href);var%20ifr=document.createElement('iframe');ifr.style.position='absolute';ifr.style.top=10+'px';ifr.style.left=10+'px';ifr.style.width=450+'px';ifr.style.height=100+'px';ifr.style.border='none';ifr.src='http://www.facebook.com/plugins/like.php?href='+url+'&show_faces=true&width=450&action=like&colorscheme=light';ifr.scrolling='no';ifr.frameborder=0;document.getElementsByTagName('body')[0].appendChild(ifr);}catch(e){}})();

Then you can visit any webpage and "like" it.

I think the confusion centers around the phrase "liking something gives them permission to write to your status feed." I first read that as "liking something gives them permission to publish updates as you." Which is similar to how some apps will get permission to publish as you, but what I believe the author means, is that liking will let the liked page publish their own updates, and you will see them in your personal feed.