Banks and Interest Rates

I'm trying to understand something, and each time I really delve into the subject I just get irritated and sad. I am trying to figure out how the banks come up with their arbitrary rules about who to give credit to. When I was 19, irresponsible, and somewhat retarded they rewarded me with credit cards. They gave me credit without question, raised my credit, cheerily rewarded me with more credit even when I failed to manage a $300 limit. 

Now, at nearly 30, my credit score is well over 150 points higher than it was, I have no delinquent accounts, I have taken care of all my old accounts from ten years ago, I make way more money that I did, and low and behold! They take credit away from me. They raise my interest rates. They tell me snidely on the phone that there is nothing they can do about it. "Sorry, ma'am. It is computer generated, and it doesn't look like there are any offers for lower interest rates on your account. Please try back next month." 

Sorry, ma'am. There's nothing we can do. It is computer generated. 

And they still extend credit to 19 year old losers. (No offense. I was one once.) 

Aren't there rules in place for this kind of blatant ridiculousness? I am the first person to admit when I screw up. I admit it. I screwed up my finances when I was 19 - 22. But now I am doing fine. 

A little over a year ago I received a credit card from my bank with my highest ever credit line. I have paid the card on time for over a year. Never less than twice the balance. Never late. And then one day they cut my credit line by over $1000. What did they say? "Sorry, ma'am. There's nothing we can do. The computer found something that was off on your credit report." 

Sorry ma'am. My ass. They give higher lines to people who miss payments. 

I'm getting irritated. I'm done talking about this. But I am going to leave it on this. 

Would our society be a better place if our banks and institutions were smaller? If the bankers still knew us by name and knew where we worked would the "dire" situation we are in as a nation be a bit easier? Less "dire"? If we had personal relationships with the people in our community who help us with our cars, groceries, taxes, banking, and child rearing would our lives make a bit more sense? Would we be a bit happier? 

I don't know the answer to that, because of course there are negatives and positives about every environment. I do know that if someone knows you they are going to try to help you out. 

And then, if someone took the time to say, "Sorry, Melissa. Your financial history just doesn't allow me to lower your rate. But please come back and talk to me, Jane, next month. We'll see what we can do." And then I wouldn't mind getting the shaft. At least I would understand. It is difficult to understand the logic of a computer.