"This is a great remainder [sic] for all users not use the same password for two different services."
Not it's not. Not even slightly.
The amount of mental effort required by users to memorise a different password for every internet site is at best unreasonable, if not a completely insane idea. While using the same password for Hotmail and internet banking is really not a good idea, using the same password for wordpress.com and wordpress.org is just common sense for people who don't have a photographic memory.
Blaming the user here is unreasonable.