You make an interesting comment about the larger brokers. In my area there is one that is, relatively speaking, bigger than the other 'big fish', but there are

You make an interesting comment about the larger brokers. In my area there is one that is, relatively speaking, bigger than the other 'big fish', but there are probably three or four "significant" brokerages, and a lot of smaller ones too. What is it about the market that causes nominally entrepreneurial people (they're commission-driven after all) to tie themselves to a large brokerage that will eat a lot of their earnings?