i have unknowingly bought bootleg dvds on ebay a few years ago. they were harder to find, foreign dvd's... and the auction listed stock photos. seller had good feedback, and i've never had any problems with fakes/bootlegs on ebay at the time. unfortunately, the seller was naru'ed before i could do anything about getting my money back.
but no, i would never ever knowingly purchase bootleg dvds. i've gotten dvd's as cheap as $3.99 during black friday sales at Best Buy or Circuit City anyway.
as for downloading... i only download stuff not easily accessible here. i watch lots of Korean tv shows (variety/dramas/entertainment news) and movies... but i do end up purchasing many of my favorite dramas on dvds. they are expensive, and i can only get from legit online retailers. occasionally i will look on ebay, but there's so many bootlegs, it's frustrating to even bother sometimes.