An anonymous reader writes: Most of us are aware by now of the myriad internet games created not for their own sake, but as a marketing tool for another product. But we're not the target audience for these games — kids are. New research out of Radboud University found that two-thirds of all kids around primary school age play one of these games at least once a week, and almost none of them are aware that they're advertisements (abstract). Worse, the game-ads are really effective. "..shortly after playing a game with an embedded food advertisement, children ate 55% more of the candy offered to them than children who had played a game with an embedded toy advertisement." The researchers further add that "it does not matter whether the games are about candy or fruit: children eat more candy after playing a game involving food."