Public and private stalls...

If I had 30 stalls, 10 of which were filled with my horses, why would there be an option to have 30/30 stalls public? Does it really mean 20/30? Is it a bug?

It really just allows you to reserve stalls for your own use. You can use any of the stalls yourself, but if you have all 30 stalls available for public use, someone could board their horse in a stall your horse vacates.

For example, if you have 10 horses of your own in your own stalls, but have it set to 30/30 public, then if one of your horses dies of old age or is sold to someone who boards elsewhere, that vacated stall can be used by a boarder. If you have it set to 20 public, then you have 10 places always reserved for your horses. You can still put your own horses in your own stalls even if you have all of them set to public.

At least, that's what I've figured out from it. I could be wrong.

Confirmation, Stash is totally right!

Ohhh okay I get it now. Thank you both!!