Both of those rates are real (I have, in fact, had exactly that salary and charged exactly that rate at different points in my career), but freelancers don't make $300k per year in any but the rarest cases. Part of their pay derives from the volatility of their work. Freelancers don't work 8 hours a day, 5 days a week - they work on whatever schedule they can according to the volume of projects they pull in. Generally, the total number of hours adds up to much less than that for a salaried worker, so the overall pay would be comparable.

Naturally, the range for freelancers varies much more widely, with the most active freelancers making serious money, and the least just scraping by.