Andrew has a dog named Chomper. Andrew isn’t as stupid as to use his dogs name anywhere as the answer to a password recovery question, but he doesn’t see why he should keep the name secret either. After all, he loudly calls his pet by name on the afternoon walks for everyone in the vicinity to hear. What harm could possibly come from posting a couple of selfies on the “proud dog owners” group on his preferred social network?
Well, for starters, in most municipalities, dogs need to be licensed, costing the owner a yearly tax. Most municipalities are also notoriously underfunded and some of them get rather creative/desperate when it comes to tapping into new sources of revenue (can you say “speed trap”?). See where this is going? If not, then here’s a business idea: compile a list of dog owners by scraping social media profiles/groups. Then offer that list to dog food manufacturers as well as municipalities for comparison with their tax records (for Andrew this spells trouble. Even though he duly registered “Chomper”, he did so under the dog’s official name and can now expect having to deal with a hearing).
Companies don’t spend money on learning arbitrary things about you. They invest in acquiring marketable information. Just because you don’t see how anyone could cash in on that knowledge, doesn’t mean you won’t be footing the bill in the end. Whatever you put on (public) record always has a chance of eventually biting you back (usually in surprising ways).