Not just leftists by any means. There are people who want to tell other people what to do, and there are people who want to be left alone. Unfortunately, the latter group is generally content to leave other people alone as well, so all the bureaucratic jobs get occupied by the controllers.
The overwhelming majority of those bureaucratic jobs have absolutely no warrant in the Constitution; some are even explicitly forbidden by that august document.
Yet they exist anyway.
The Anti-Federalists were right.