Caveat: normal people don't care about such things.
How many people become victims to identity theft per year? How many people end up in a bad breakup where their ex uses private information in some action of revenge? How many people get falsely accused each year by the police?
Ask them if they care about privacy and anonymity, or as it is more commonly phrased, personal security.
Also, the whole "once it happens to someone, they care" applies to pretty much anything. Find someone who invests a lot of their time speaking in public for any cause you can imagine. Someone who talks to audiences about the perils of alcohol, drugs, any cancer or disease - basically anything that is harmful/dangerous/deadly. How many of them do you think ever gave a second thought to their cause, before it affected their lives personally (themselves, a family member, or close friend)? Practically none of them. People generally don't care about the consequences of anything until they've been slapped in the face by it.
People care, they just don't know.