My whole nuclear family uses find my. More than once I’ve helped give my wife directions by watching her dot on the map (Apple Maps had some problem). I regularly use it to pickup the kids when they have been walking around town. Rather than texting me their location every time they move, I just get directions when I leave and let them know when I’m close. I mean, at least a dozen companies know my location at all times (Apple, Verizon, Weather.com, Google, Tile, etc) so hardly an issue for my family to know.
As far as stalking or surveillance, I mean most people live very boring lives so watching them go from home to work or school: you have to really have nothing going on.
Ironically we do a lot to defend our privacy, such as kids not having any social media. I just pick my battles and recognize those I have already forfeited (I mean we could just use get walkies and speak in code, which we did before kids had cell phones).
As far as stalking or surveillance, I mean most people live very boring lives so watching them go from home to work or school: you have to really have nothing going on.