I had always heard, and thus assumed, that Pringles were not classified as potato chips because they were prohibited from doing so due to their mostly non-potato make-up. It’s well known that Pringles are not manufactured like ordinary chips. As opposed to being made from whole potatoes, they are formed from a type of potato dough containing less than 50% potato content and then baked.
However, it turns out that the truth is somewhat different from popular belief (imagine that!). According to this article by the BBC, the fight to have Pringles classified as a “cake or biscuit” was led by Procter & Gamble (the parent company of Pringles). The reason? Potato crisps (chips) are subject to a 17.5% value added tax (VAT) in the UK, whereas cakes and biscuits are not. By having the snack food de-classified as a crisp/chip, they were exempt from paying the tax. This just goes to show that often times the truth is much more straightforward than people make it out to be and reinforces the notion that if you want to find the underlying cause of an issue, you should “follow the money”.
Also of interest, according to a more recent article, the decision has been reversed on the grounds that the 42% of Pringles batter made from potatoes “is more than enough potato content for it to be a reasonable view that [Pringles are] made from potato”.
So what should we conclude from all this? No matter what you thought you knew about Pringles, you were probably wrong.

I had heard about this with regards to soft cookies trying to get themselves considered small cakes. They baked a big version of their soft cookie to demonstrate how cakey it was.
How soon will you update your blog? I’m interested in reading some more information on this issue.