(wow it's been too long, lol)
I think the reason they were effected was simply because many of Voldemort's followers had house elves. The malfoys probably were not the richest of the deatheaters, and if they were, i'll bet crabbe and goyle, and maybe nott's family was pretty rich too. I'll bet most of the death eaters had house elves do the dirty work for them, and because death eaters are terrable people by nature, their elves probably weren't fiven the "star treatment".
If you can't find me here, chances are i'm out looking for my coffae coolata.