The money is fair - around 55k per year in the midwest, but sadly it doesn't go up much from there in the big city. Since thousands of people want these jobs, and the job itself doesn't directly produce revenue, the money will really never be big unless maybe you write a book and people care enough to buy it.
Some curators at the top of their game can make in excess of 85k, but it's rare. On the other side of the coin, there are plenty of curators who are just scraping by on an income of under 30k.
The highest-paying curator jobs are to be found in federal government agencies. If you can't get into one of those, your next best bet is employment in academia, or in a state or local government agency. The lowest rung of the ladder is the curator at a museum or historical institution, which is a shame, as that job is arguably the most interesting and engaging.
The gig takes a lot of hard work, a sensitivity to museum donor politics, a wide range of expertise and many years of schooling to get there. And, unfortunately, there is no hazard pay for the stuffed animals in the museum coming alive and trying to attack you at night.