Most anime fans in the US either grew up watching things like Robotech, G-Force, and Voltron, or for the newer generation: Pokemon, Yu-Gi-Oh!, and Digimon. Anyone else typically gets into anime because he/she has a friend that introduces him/her to it.
I remember both Voltron and Pokemon broadcast on Russian TV channels. I liked Voltron back in my childhood, except I had no idea it was called "anime". But seriously, apart from Voltron, there were Robotech, Wonderbeat Scramble, LunLun, Transformers Masterforce, Sailor Moon... not to mention a number of anime-adapted classics like The Wild Swans.
Nowadays? It's mostly Naruto, Naruto and Naruto. With a bit of Shaman King inbetween. Occasionally some Miyazaki, except that nobody including himself considers his films "anime". There were some other series, sometimes broadcast on music channels, of all things.
But in general, you have to be introduced to anime by someone before you so much as start hearing about things like Evangelion, Death Note and Haruhi Suzumiya. Anime has never been advertised to the broadest audience to begin with. Unlike Japan where all probably 90% of animation can be classified as anime in the sense western anime fans understand the term, here in the west children don't get introduced to it early. And even when they are... Naruto just can't appeal to everyone, can it?
It also doesn't help that the pervading perception among the populace (wow...I've never used alliteration that well before) is that anime = cartoon so it must be for kids.
I heard of a girl who looked at Madoka cover and immediately assumed it was like WinX.
I dislike this prejudice a lot, really. Atlantis and Treausure Planet, both being MARVELOUS Disney animations, owe much of their commercial failure precisely to the fact that they were teen-oriented, but teenagers didn't care enough for "Disney cartoons" to go to the movies specifically, and the company did little to nothing to properly advertise them (ever since Shrek, they were prepared to throw 2D out the window anyway).