The new Universal park goer, so-to-speak, is generally a Harry Potter fan or a Simpsons fan. And then they get to the park, and they see how many other great things there are, and that's how they become a Universal fan.
Universal is doing what Tony Baxter wanted to do at Disney for years, which is to bring in newer different brands that people already love, build something amazing based on them that you'd absolutely *NEED* to visit, and those people will see all the other neat things in the parks and realize that they're also a fan of that entire park too!
Tony did that with Indy at Disneyland. Now Universal is doing that with EVERYTHING at ALL its parks. Those people aren't going to Universal just because they want to be anti-Disney, they're going there because they already love Harry Potter (or some other property that Universal has in its parks) and they want to live the experience in that property.
And for the locals, well, it's about what parks are treating the locals the best... AP events, seasonal events, ease of access, and all that jazz. And Universal is winning that battle right now.