How Stupid do they Think I Am?

Ever since I've been a homeowner, I've been innundated with offers to refinance my home. I need to start off by saying that I originally bought the house when interest rates were very low, and I was wise enough to refinance when rates were at their rock bottom. Despite the fact that interest rates have consistently climbed since I refinanced, I am still barraged with "offers" from mortgage companies, where I am told that I can "save" money on my mortgage payment. How can they do this? It's easy, they're asking me to give up my low, fixed-rate mortgage and take on a variable-rate mortgage. In return, they'll give me a teaser rate for a few months, thus "saving" me money over the next few months, only to sock it to me later. How stupid do these lending companies think I am? Maybe a better question is, how many Americans really are stupid enough to fall for this sort of crap?