For a lot of people it is as simple as not allowing certain companies like Google, Amazon, etc (to collect data on you who turn around and sell the information). Also, if you are using your phone, laptop, or tablet on a public wi-fi, it helps protect you from things like man in the middle attacks and just other people gaining access to your device and getting other info. It can help secure your emails (although if you are using something like gmail I am not sure it matters). It helps eliminate location based advertising if you don't like that kind of stuff. Plus it allows you to do internet searches without fear of someone watching. I know the last one is a little controversial, but if you live in a place where you believe that Big Tech, the Government, whoever, is watching...it adds a little bit of piece of mind. It's not an absolute, mind you...but it is a good start.
