they may be public figures does not mean we should have access to their private lives. Personal information should only even be given out with the person’s consent.
Ways to overcome this ethical issue would be to use cameras and other observation tools on inanimate objects only. The text gave the example of observing whisky consumption by using cameras to count empty bottles in a trash can. This technique was described as “dry”. In my opinion the only way to overcome the issues with ethicality would be to use the tools described in only “dry” manors.
If the observer wanted to look at people, and their daily interactions, they should only be allowed to take volunteers. Another way to access information is on social media. If the person’s profile is public then obviously, they are condoning the idea of being observed. As long as they are aware of this, it should not be deemed unethical. In other words, if people were told why being observed in day-to-day activities is important to the sociological communities, people may be more open to the idea and give their consent to help conduct research.