How to avoid being photographed in public?

Near where I live and work, there are sometimes people passing by taking pictures. Some of them appear to be tourists, while others might be locals taking pictures for fun or for work (e.g. photojournalists). Some people even take pictures inside malls.

As much as I can (and of course, within the bounds of reason), I don’t want a stranger to take a picture with me in it. I have no problem having my picture taken when I want it taken (e.g. birthday parties, special events, etc.). However, I do not want a picture of me in an unflattering pose to circulate on the internet. Plus, there have been instances where a person’s picture was used in an unauthorized way to communicate a message that the person might not agree with.

See http://blog.chron.com/momhouston/2011/04/texas-anti-abortion-group-sued-for-using-girls-photo-in-ad/

https://aattp.org/woman-whose-image-was-used-without-permission-to-smear-obamacare-calls-out-right-wing-liars/

http://teachingsofdrjim.com/courses/molina/ (Alison Chang story)

(Note: examples for illustrative purposes only and are not intended to show positions that I agree or disagree with)

So, my question is: What are some ways that I could avoid being photographed in public? I am looking for rational approaches to avoid being photographed in public. For example, simply not being in public is not an option due to my work. Also, wearing strange disguises will also not be an option as it will probably cause more harm than good.

Looking forward to seeing your responses.

P.S. I am aware that surveillance cameras might be recording people and might therefore be taking pictures of me all the time. I am not concerned about surveillance cameras, as the pictures taken by such cameras are usually for internal use by a particular business or government entity and are usually not posted on facebook or other social media.

P.P.S. A related question: Is there a good way to tell someone politely that I would prefer not to be photographed?