I think if Walmart were to start using political influence to shut down competition like standard oil was doing, it would have to be broken up.
And Ma Bell was a regulated monopoly to begin with, so that had to change.
"I have worked in a small bank and they most assuredly do not have huge profits."
Profits aren't really the issue for most companies imo. Its out of control bureaucracy. Like they will have 6 people making 120k a year, having endless meetings on things they have no real world experience with. Whereas Walmart has managed so far to avoid the bureaucracy, and give its management on the front lines more power.
Which a small bank usually doesn't have problems with bureaucracy. I know I now go to a small bank, and am very happy with the customer service, all the products and financial services they offer, and prices.