PTFE Sticks To Nothing, How Does It Stick To The Frypan?

This is the chemical structure of PTFE, the blue circles are Carbon atoms and the red circles are Fluorine atoms. Because of the particular structure, PTFE sticks to itself but not to anything else, which is why it does not stick to food. Not even geckos can stick to PTFE. Carbon-Fluorine bonds are very hard to break which is why PTFE is so strong.
So if PTFE sticks to nothing, how does it stick to the frypan?
There are steps to making PTFE:
First the aluminium pans are cleaned with an alkaline solution using a high-pressure hose. Then it is aired and dried. Next up is grit blasting, this is where iron particles are sprayed on