There's a lot of talk about strategy for keeping your settlements fully stocked and defended, but haven't seen any explanation of WHY. And not even in that philosophical "what really is the point of playing ANY game?" sense, just "what is the worst that could happen if you leave your bases completely defenseless?".
Do raiders destroy buildings and/or steal items you have stored at your workshop benches? It's not like the FOBs in MGSV, where you could boot up the game one day and find that everything you've been hoarding over the last dozen hours has been jacked, right?
Or is the whole settlement aspect mostly a "for fun" thing?