That's not surprising at all. From an economic perspective, people choose jobs to maximize utility, salary being just one component of that. They don't have to pay them that much because being an astronaut is literally one of the coolest jobs ever.
In addition, the demand for astronauts is astronomically low :), so the supply of people wanting to do it is very high compared to demand.
Think about scuba diving instructors. They don't make that much money because it's such an awesome job. If I could make 150k a year doing that, I would quit my job in a heartbeat, move to Hawaii and never look back. However, they don't because if they started paying that much, a million other people would do the same, flooding the market with scuba instructors which would shift the salary back to what it is now.
In addition, the demand for astronauts is astronomically low :), so the supply of people wanting to do it is very high compared to demand.
Think about scuba diving instructors. They don't make that much money because it's such an awesome job. If I could make 150k a year doing that, I would quit my job in a heartbeat, move to Hawaii and never look back. However, they don't because if they started paying that much, a million other people would do the same, flooding the market with scuba instructors which would shift the salary back to what it is now.