I think companies are more than willing (generally) to pay good rates for freelance services. It's up to the freelancer to justify what they charge, whether it be displayed by expertise, experience or anything else. If you can prove value in the service to your customer (and what they will actually gain from contracting you), they will (mostly) pay.
I don't see too much difference in freelancers and big companies other than the overhead cost. The only reason the big companies have to charge so much is because they have big buildings, employees(freelancers) and lots of advertising to pay for.