What he said.
Different parts of Disney may be designed to appeal to different market segments, but Disney pretty well has something targeted to every segment. In fact, one of Disney's biggest problems is probably getting the word out that Disney has products and services to appeal to every market--not just families with young kids.
Getting back to your question... if you just think of those two segments (kids vs. moms), it's got to be the moms. Moms decide to spend the money; moms want special experiences for/with their kids. Kids may see something and say they want to go, but Disney has to convince the moms that spending the money is worth it. Of course, the end result is still a great time for the kids, but here is an interesting thought (at least to me): does Disney offer/advertise things that kids like/want the most OR do they offer/advertise things that moms want most for their kids?
The answer is likely too simple: they do both... or maybe work on the overlap between the two to maximize ad $$...