I think he's most likely considering the worth of the material that goes into it. For ex. you can buy approx 5 pounds of HP multipurpose paper from Amazon for $6.78 with free shipping (http://www.amazon.com/HP-Multipurpose-Inkjet-Brightness-1120...), while a Moleskine weighs probably under 0.2 pounds, including the covers.
He's probably considering the fact that there are other high-end notebooks that cost the same or less, filled with paper of a much higher quality. Keep in mind that a person's personal preference will play a large role in how that person judges a paper's quality.
There's Clairefontaine, Black and Red, Rhodia, Leuchttern, and probably a dozen or so others that I'm not aware of. Some might be a little more expensive than Moleskines, but some of them are much cheaper depending on the size and model you prefer.
My Muji notebooks are $3.5 a piece for 80 white A5 pages, with a solid cardboard cover and a ring binding (which I personally like better than the "traditional" binding). A 192 page Moleskine is $13 - 50% more expensive per page, and they don't have a ring binding.
Also Muji is a Japanese brand - the paper works really well with fountain pens, which are common there. Moleskine paper does not fare as well (as fountain pens are rare in the US). Being French (one of the few remaining fountain pen heavy cultures, with Japan and Germany), I still write daily with a fountain pen and deeply enjoy it.
Oh and also I'm left handed, and thus write in my notebooks from last to first page (in western order) - since Muji is a Japanese brand, the notebooks are designed to be used in that way. That's a little detail, but I'm a little obsessive :-)
I'm left-handed too, so I'm intrigued by your note taking. So you flip through notebooks 'backwards'? How does that help with any of the problems left-handed people have with writing (eg smudges)?
It helps in that I don't have the metallic ring spine digging into my hand (I only write on the recto of the pages. I guess I could write from left to right and write on the verso, but that feels weirder). So this is what my notebook looks like:
http://i.imgur.com/SSc29KLl.jpg the page flipped over to the right being the previous page, and the page under the one visibly written on being the next page.
Sadly, I still have to be careful when I write, otherwise it is a smudge fest (especially with a fountain pen; fortunately, I had a few grade school teachers who taught me how to write with my hand positioned in a way that minimizes smudges)
Your argument about which kind of writing instrument is popular in which country is very interesting, but you seem to think Moleskine is a US company? In fact they're from Italy. Not sure if that changes your reasoning, but it might be worth mentioning since you seem to not be aware of it.
