The Customer is never ... right?

I'm beginning to hate credit card companies. I like credit cards--as long as they're controlled--but I really hate the companies that issue them. Whatever happened to true customer service? How about making the customer happy? How about just a little honesty and fairplay? None of these seem to matter anymore.
I've heard horror stories about credit card companies and how they act toward people, but I guess I thought I was immune. We've been with the same credit card company for almost ten years. I thought they were good to us, but just recently am I discovering the different things they've been pulling through the years. For instance, we paid off a substantial amount with them last month after we sold our house. I went online and got the exact amount we owed so that I knew how much to send. Then they told us there was a finance charge that needed to be included AND a late fee. I paid the bill online, on their website, on the due date. But they said since the due date was a weekend, it wasn't posted until the following Monday and so it was late. And finance charges keep accruing until they receive payment. I raised a stink and they finally waived the late fee and additional finance charges. Then I told them to cancel one of my cards. I had them check first to make sure I had a zero balance. Two weeks later I was battling with them again. Not only had they NOT cancelled the card, but they had also added some finance charges there as well.
This month I was also almost late because they keep changing the due date for payments. Somehow it creeps forward a few days each month. Well, last month they said if I had paid by phone, it would have been recorded immediately. So this month I called and told them I wanted to pay by phone to avoid a late charge. The man said I was already late and a late fee had already been charged to my account. I asked how that could be when I was calling ON the due date. He said the due date was on a weekend and I needed to pay by the previous Friday at 5:00 p.m. or I was late. So now they charging me a late fee for not being two days early. The man on the phone didn't seem real upset about the late charge. He was too busy trying to convince me to take advantage of their zero interest rate on balance transfers. I told him I wasn't interested, and then he pushed, saying they had checked my credit report recently and he could see that I had some balances I could transfer. Wait a minute. You pulled my credit report? Without my knowledge? He assured me they had a legal right to do so.
Now I feel weird. Who are these people I'm borrowing money from? I feel like I made a deal with the mafia. I'm looking around for another credit card company. In the meantime, I'm paying my bills a week early. I wonder if there's an early fee as well.