I can't recall any time I have seen a public restroom with a knob to exit instead of a push or pull handle. Even office buildings don't have a knob on the door.

The closest I've ever seen is train and airplane bathrooms where the knob is required - but it is also close enough to the sink that you just use your towel and throw that.

There are knobs on the stalls, but you wash your hands after exiting the stalls so I don't think you are counting that.

* giggles in British.