Well I think you're partly right, but there is more it. Corporate media conglomerates tend to have lots of right-wing personalities not only because of money, but because they are less likely to upset advertisers and/or the general status quo. Conservatives tend to be much more corporate friendly then progressives. It's much too complicated for me to explain here, but if you're interested, I highly recommend
this documentary.
Democracy Now! is not like any other news organization. They are independent--they don't advertise or accept donations from corporations or governments. The program is entirely funded by listeners so they are much freer to report on whatever they want.