I assume it was pretty obvious that there was a sponsor for this contest - that it wasn't just you offering the prize. People should have been able to figure out that the purpose of providing the information was so that the sponsor of the contest could contact them. But as P.T. Barnum said, you don't get rich by overestimating the intelligence of the American people. Next time, I suggest explicitly informing them that their contact information will be passed along to the sponsor of the contest, and that the sponsor may contact them afterward. (And be sure that, like this time, the marketer is ethical enough to include and honor an "opt out" link on any subsequent email.)

