I can't give a super accurate history of how we got here, but it seems as though it's been a gradual process. Once the banks saw that people at bars, casinos, and high end hotels would pay these 'convenience' fees, they said to themselves, "why not do this everywhere?"
It also ties in to how banks are regulated. Now again, I'm not super well versed in the history here, but as I understand it, after the stock market crash in the 20's, congress passed the Glass-Steagall act which, among other things, said that the banks either had to be an investment bank, or a commercial bank, but not both. That way the commercial banks, which are holding regular folks money, can't gamble it all away. That seemed to work pretty well, so much so that congress was later convinced to repeal large portions of Glass-Steagall.
Once that happened, investment bank culture, which never really left commercial banks, once again came to prominence, along with it's emphasis on making money for shareholders.
The reason I mention all that is to say that during Glass-Steagall commercial banks had to go back to making money slowly but surely through giving out safe loans and charging modest fees for basic services. In the meantime, their shareholders, having had a taste of the large dividends generated by investment fees and the like, came to expect more than the safe, modest returns commercial banks used to provide. In order to appease investors, commercial banks then had to look for other ways of generating profits. That's where things like atm fees, excessive overdraft charges, monthly checking account fees, and the like come in.
The fees and stuff actually got so bad that congress passed a law mandating that the banks had to allow people to opt out of overdrafts, among other things. Unfortunately, this law had been kicking around for several years by the time it got passed, so the banks had plenty of time to weaken it and/or find work arounds. For instance, where you used to get a single overdraft charge for each time you overdrafted, many banks went to a system where you got a daily charge for every day your account was in the negative. I've literally seen someone crying in the bank upon being told that what should have been a single $40 charge had grown in the course of a week or so into a $400 charge. Sadly, this is just one of many such examples of how commercial banks have changed their practices to prioritize profits over public service.
Hope that all made sense. As I said, I'm not a historian, and a lot of the stuff I discuss is widely debated, but if you find it interesting there's a lot of good info on wikipedia and youtube, not to mention your local library. :)