Lego seems to have plenty of ads at least in my area. If you watch kid's cartoons in the 5-9 age bracket you'll see a lot of their ads for special packs like Lego Space Adventure, etc.

Apart from whatever official marketing they do, they're also simply a very well-known and well-regarded brand. Even the word "Lego" is basically synonymous with the whole market segment they're in.

Finally, Lego sets are just addictive (as I remember well from my childhood). I think I got my first one by accident--it was a tiny $3 (or something) set because the matchbox cars I liked back then weren't available. This was years ago so the details are fuzzy, but I still remember which set it was :) After that I was completely enthralled by Lego and continued getting more and more for years. Ultimately, the only reason I stopped playing with them was because I got even more addicted to programming. That alone must supplement their conventional marketing by a large amount.

McD made a boatload from a teeny beanie babies promotion:

"Estimates suggest that McDonald's made $250 million of sales on Teenie Beanie Baby Happy Meals during this promotion."

Link: http://www.associatedcontent.com/article/1460556/mcdonalds_g...

Maybe the kid brought home an all "A" report card and the parent wanted to do something nice. Or not. Probably not. But I've been known to reward my kids with something they want if they have done something deserving a reward.