Probably an instance of this?
[T]he obvious giveaways are used as a pre-qualifier, to ensure with the least possible effort that the ONLY people who respond to the scammers' initial mass mailings (and therefore have to be brought along individually during the later stages) are the absolutely most gullible, ignorant, susceptible, suckers they can find.
http://www.quora.com/Scams/Why-are-email-scams-written-in-br...