First of all, Corocoro Comic is a right to left magazine, because the major contents, which are the manga, is written vertically from right to left, just as all manga are.
As for your example, pages 8 and 9, that's a special page which is something like an ad. But still, the basic information on those pages is written vertically (hence right to left). Meanwhile, the side information is written horizontally (hence left to right). This layout was probably intentional. At a glance, the readers can sense the difference between the main stuff and the side stuff.
Or, okay, perhaps "main/side" isn't the correct way to express it. The story-line-y stuff are written vertically and for more details you read the horizontal stuff.
On a side note, however, the older generations are less comfortable reading pages like these. For example, people currently 80 years old or older prefer to read vertical writings over horizontal writings. People in their 70s are totally comfortable with both, and yet, when they read manga as dramatic as the ones in Corocoro, they have trouble finding which way to go. They are more used to the so-called 4-koma-manga like the ones you see on the newspapers, but are often puzzled with action-type manga for teens.
And nowadays, school text books' layout is very much like manga magazines. Just on one page, information is scattered here and there, vertically and horizontally. It wasn't like this 30 years ago. Text books used to have plain writing written on it, and perhaps there was one or two topics or graphs on the corner. Nowadays, a character may be talking into a "fukidashi" bubble about history heroes, while 3 different colors divide the page into random boxes.
So what I'm saying is that, even in the past few decades, the Japanese way of comprehending the layouts has changed dramatically.
By the way...
I've noticed more and more Japanese people saying that books are right to left because it's more comfortable to shelve pages left-to-right for right-handed people.
Being Japanese for all the 51 years of my life, this is the first time I've heard of this theory. However, writing from right to left had always been practical for those writing symbols of Chinese origin, because writing was done holding a brush with your hand and elbow up in the air. On the other hand, in Europe, writing was done with your wrist touching the ink on the paper, so it was better to write from left to right avoiding the ink to smear.