I think the Arabic ones etc rather would have switchable ROM sets than more RAM. Of course, if you count the total amount of ROM, you can say it got more memory even if only a part of it can be used at a time.
Regarding the CPC 472, it was only sold in Spain due to a regulation: computers with up to 64K RAM were required to be localized in the Spanish language, including the keyboard and screen messages. Therefore Amstrad added 8K of RAM that is unaccessible to bypass the regulation... However, later the regulation was changed to include all computers, no matter how much RAM they had, so therefore it exists localized Amstrads as well.
A rather tough decision by the Spanish really, to enforce that all home (?) computers sold within the country should be in Spanish. I wonder how many brands who didn't establish themselves for that reason, given how much work and costs it would be to localize the computer. On the other hand, if this regulation was effective from circa 1985, most smaller brands had already dropped out of the market and only the bigger names remained. Computers such as IBM PC, Apple Macintosh, Commodore Amiga, Atari ST and so on probably were easier to localize as they all have plenty of RAM and most of the operating system (and fonts?) is loaded from disk. Add a few symbols on the keyboard, and off you go. Smaller, mostly ROM based 8-bit computers I suppose were more work to adapt both character and OS ROMs, plus keyboard of course.