The median household income in the States was 55K in 2016 (
https://www.census.gov/library/visualizations/2016/comm/cb16-158_median_hh_income_map.html). So, if a pro is making 50K a year he is doing pretty well considering about half of the households (not individual earners but households) in the country make less than he does for jumping around on his skateboard.
As for skaters who have serious money, it is likely few and far between. Rocco walked away with some serious money, Pierre from Sole Tech has some serious money, Dyrdek is sitting on some money (despite not having a soul), Jason Lee got some serious money from being in movies, and of course Tony Hawk.
Then I'd imagine the mainstream guys are next on the chain Sheckler, Nyjah, Pudwell, P-Rod, Chris Cole, D-Way, etc.
Then TNT, Busenitz, Janoski, Mayhew, Steve Cab, etc. are probably pretty comfortable and don't really need to worry about money.
And then there is everyone else who are going to need to find real jobs.
But, hell, even if we go with Ryan's number of 24K, I'd be stoked if someone paid me 24K to travel around the world and skateboard (well as long I was not riding for Zero and dealing with the Chief expecting me to wear the emo uniform and expecting me to kill myself for pennies while he remodeled his house on the beach).