How Dumb Do They Think I Am?

I received some mail from the ANZ bank yesterday. That seemed a bit unusual as it was a bit early in the month to be receiving mail from them. I opened it and it began like this:

"Dear Mr Ham,

To thank you for being one of our best customers....."

At this point my suspicions were raised. And they continued by offering me the low interest rate of 9.50% for the first six months if I borrowed any amount of money above $500 against my credit card.

As if I want to borrow money against my credit card. How stupid do they think I am? I get the feeling that lots of people will fall for this and I think that it is a dirty, underhanded trick. I hope the two banks that I have shares in don't follow the same path.