The sink faucet
Before you can wash your hands you have to turn on the water, which means turning knobs that thousands of other hands in need of washing have turned before you. Combine that with the excess water that tends to pool up around faucets and you have the perfect breeding grounds for mold, mildew, and bacteria to thrive. It's enough to make you grateful for those annoying auto-turn-on faucets.
The soap dispenser
The manual soap dispenser is another bathroom objet d'art that will make you thank whatever higher power you're into for the modern technology behind sensor-operated soap pumps, because ugh, are the lever mechanisms on soap dispensers ever gross. Not only are your filthy hands getting all over it, but you've probably already added some hot water to the mix, turning your paws into germ soup.
The bathroom door handle
Sure, you washed your hands before heading out of the bathroom. (You did, right?) But let's level with one another: Not everyone is as diligent about proper hygiene as are you. Which means that Bob from Accounting, or whoever the notorious not-washer in your office may be, is blowing out of the restroom after his morning blowout and putting his disgusting, unwashed hands all over the doorknob, handle, or push plate. Just like with the toilet flusher, the door is a good place to opt to use your foot, rather than your hands, to do the work.