I think you hit the kernel of the argument in the first paragraph: If you have an obscure pet cause, then chances are it’s because you do have some special knowledge about the problem. The person visiting a random village might not, but the locals do, and hence this is a reason why local charity can be effective, particularly if you live in a remote area where the problems are not quantified (and are hence probably not reading this).
I think you hit the kernel of the argument in the first paragraph: If you have an obscure pet cause, then chances are it’s because you do have some special knowledge about the problem. The person visiting a random village might not, but the locals do, and hence this is a reason why local charity can be effective, particularly if you live in a remote area where the problems are not quantified (and are hence probably not reading this).