I wouldn't sweat it. A nice traveller/passer by put down a boat sign for me. I had lots of stockpiles sitting around. I logged out, literally for 5m to fix some router settings. I logged back in, someone had swung by, taken my stockpiles and logs to build the boat and rowed off. I was impressed

. Easy come easy go. Nothing to lose sleep over.
To be fair, I was at a temporary base I had set up just to quick up some clay, so it was in a high traffic area. I was still amazed it got snatched that quickly. I foolishly thought leaving it 95% unbuilt would be a deterrent 8). People take stuff. People steal stuff. Until you have at least Yeomanry, don't even worry about keeping things. Small knick knacks you can put in a bin and stuff in your leanto, and be reasonably certain it will be there when you get back (assuming your hearthfire is near your leanto. I've yet to have my leanto robbed, not that I keep anything overly valuable there. Overall, don't try to have nice things until you have nicers skills and nicer still walls

. But, YMMV.
Oh, and by the way, those guys almost certainly couldn't have murdered you. Too expensive this early on. Odds are, if they could have, they would have. In my experience at least.