I never dry my hands after washing them in a public toilet.

You may as well not bother. After all, even if you do wash your hands, you then have to grab a filthy door handle to get out of the bogs that hundreds of super-unhygienic people have grabbed before you. You've probably only been in there for a wee, but you then emerge with your hand covered in other people's invisible shit. I compromise: I do wash my hands, then either (a) wait for someone to open the door from outside so that I can elbow my way through without touching it, or (b) loiter until someone else opens it from my side, then muscle my way out before it closes, or (c), if I'm desperate, use the very tip of my pinkie to try to drag it open then regard my pinkie tip as totally insanitary for at least the next half-hour. Let's face it: nearly everyone except me is disgusting.