Many of my t friends don't make much. They often work two jobs (one full time which can often be 60 hours a week), then they have a part-time job on nights and weekends. My mentor had 5 jobs at one point: one f/t position as director for an agency (with 24/7 on-call for her employees), a clinical supervisor position 1 day a week for training clinicians, her private practice on the weekends, consulting with a former agency at least once a week, and on an advisory board for the state that met one weekend every month... definitely not a glamorous or well-paid field. Even the clinicians I know who do primarily private practice also hold more than one job to make ends meet (especially the ones who offer sliding scale or payment flexibility for their clients)...
Prior to licensing/credentialing, they make even less and work unpaid internships to meet hours for credentialing requirements...
I do know a few who make significantly more money, but they work in private practice in very wealthy areas.