A Faithful Financial Customers or Fool and their Money?

In late 2014, I called my credit card company as I queried the persistent £1.17 on my credit card bill. They investigated and left a mesage telling me that the interest rate being charged on my card, was higher than it should have been. I called back and they told me that the previous customer service info was wrong. The £1.17 was interest free for life, as it had switched the rules before the amount had been paid off. Then he told me I was paying 24.9% interest on the card! I asked if they had any cheaper cards and was told "yes, they have one with 6.4% interest". "Can I switch the balance to that?"

He said he would transfer me and it shouldn't be a problem as I was a loyal customer over many years. Ok.  A few minutes later he returned saying it wasn't possible. Why? Affordibility. Affordability? So I can affrd to py 24% but not the lesser 6.4%? Very strange. I must be a very good investment, in that they are earning a reasonable amount of interest and charges from my accounts and therefore unwilling to give it up. Time to start the snowball rolling!