One reason is to keep out competition with the help of the state.
I am a fan of John Allison. I worked for the bank he once headed, and I was a fan of him then too. He made sure that every manager in the bank (BB&T) was issued a copy of Atlas Shrugged when hired in or promoted. How’s that for a managerial statement? Seeing him at AEI today, it was clear that his fire for free markets burns as hot as ever.