Really bizarre choice of photo to include in an ad. Even if the place took in a rescue, why would they put THAT photo in a general boarding ad? The barn where I board takes in rescues, but they don’t use photos of them in their general promotional materials. It’s not like he’s just a little ribby and swaybacked… Even if he’s a “senior” there’s no excuse for having a horse in that condition, other than having just very recently acquired him in that condition. Old age is not a disease. Old horses that look like this have not been given appropriate dental and veterinary care, and/or not been given feed appropriate to their needs (e.g. pelleted hay replacements for those who can no longer chew normal hay or grass adequately). If a horse dose have some untreatable/unmanageable condition, the humane thing is to let them go before they slide this far down hill.
I disagree that people should directly approach the owners in this kind of situation and ask/try to help. 1) Let’s say it really is a rescue situation, either a one-off or a more organized rescue that regularly takes in horses. Which would be more annoying/intrusive—an initial surprise visit from LAPS, show them your facilities and explain things, maybe a few check-ins later on to make sure things stay on the up-and-up and aren’t devolving into a hoarding situation; or an ongoing parade of “concerned citizens” who have seen the horse? Some of which may be totally ignorant about horses, some of which may not accept your story or agree with the details of what you are doing and keep pecking at you, etc. 2) The barn owner could well be a nut job hoarder who gets belligerent when confronted, however nicely. 3) In this particular case, sounds like the OP’s local LAPS is willing and able to provide good education and guide people toward other resources and, if needed, take in a surrendered horse (or start the ball rolling on forcibly taking a horse if the person turns out to be a belligerent nut job).