Why was the size of the chips in SA reduced?

I previously noticed that the size of the Pringles chips seem to have been reduced, but thought I might be imagining it, but on my way back from Europe I bought some Pringles at Frankfurt airport and these chips were clearly larger than those sold in SA. The only conclusion I can come to is that Pringles reduced the size of the chips in SA, but the price remained the same. I find this very misleading?