Do they keep track of how much people cross the bridge?

Non

Probably remotely

I would say no

Not on a regular basis. During vehicle and pedestrian usage analyses they collect general data, but that's it as far as I know.

They do not.

They monitor traffic across the bridge, not pedestrians I guess.

The question is what would you do if they do?

Good question. I never saw any counter when I walked on it

I doubt it