The realization that I could buy a season pass to Cedar Point, because I was a grown up, came to me about 20 years ago now. Starting PointBuzz (then Guide to The Point) came shortly thereafter. The thing that I recognized almost immediately when entering that community was that a lot of people looked at a job in the theme park business as the ultimate gig. However, the expectations about that arrangement tend to be, on the whole, fairly unrealistic. Now that I live next to Walt Disney World, I see it even more.
The first unacknowledged reality is that supply and demand tends to drive wages down significantly. Seasonal jobs at regional parks are getting a little more competitive in some markets, but if you're a college kid wanting to dispatch roller coasters, there are 30 people lined up behind you to take that job if you don't want it. The front line jobs in particular are not high skill jobs, so they aren't going to pay a ton, even if you stay in them for a long time.
That leads to the fact that there isn't a ton of upward mobility in your average park organization. Managers that did come from within tend to stay there for a very long time, and aren't likely to give up those jobs if they like them. They don't pay particularly well either, but again, there are a bunch of people who would love to have those jobs. Paying your dues isn't a path to advancement, because there isn't much opportunity to advance.
There's also a gross misunderstanding about the difference between front-end line jobs and professional office jobs. Things like finance, IT, communications, engineering and the like require experience in those areas, just as they do at any other company. Experience selling churros doesn't count. Having worked in the corporate office of a theme park company, there tend to be a lot of professional managers from different industries, and professionals from all walks of life. (There were a fair amount of B-players from another theme park company, but that's another story.)
Salaries for professional gigs tend to vary a lot by company as well. I encountered one job here in Orlando that was at least $50,000 below the market rate, and they eventually hired someone willing to take it (with matching skills and experience for that salary). On the other hand, another company pays market rate, and another pays above it.
One of my best friends was a total park nerd in high school, went to college, and within a year of graduating reached the job that she thought she wanted on the marketing side of the business. She was underwhelmed by the job (and probably the pay), and eventually found something else with greater purpose. I worked in a corporate headquarters here in Orlando and made solid money as a contractor, but even if they could have converted it to full-time, it wouldn't have been enough to keep me there. That's just the nature of the business.
I say all of this not to discourage anyone. I get the allure of snorting pixie dust and being in the business of fun. But it's important to be realistic about what that means in terms of career and salary outlook. I see young people on Twitter frustrated that they only make $10 an hour herding kids on to Dumbo, with a strange sense of entitlement that implies they deserve more. Maybe they do deserve more, but they'll never get it in that job.
I know some people who have been in the business for a long time, many of them among the best at what they do... general managers, vice presidents, directors... all-around top notch professionals in every case. They work a ton of hours and in many cases don't make as much as counterparts in other industries, but they love it. If you don't have that love, or it doesn't counter the shortcomings, it's not the business for you. If you're expecting to make a good living in a line job, I can't urge you enough to pursue a skilled career in anything else.