1. You feel that you giving to the Mercy Corps is comparable to Romney giving to the LDS church, even though Mercy Corps is obviously the superior choice for you.

2. The rest of the world has no impact on your society, but you like humans well enough to help them anyway.

I'd say that the second point might be somewhat correct, even if in the long run, a better world in general is a benefit for the american society.

But however, a church, while doing obviously great things when it comes to disaster relief and soup kitchens etc, tend to spend most their money on church related stuff, like upkeep for the houses of worship, paying their local imam (or comparable...), indoctrination education of the young, and stuff like that. I am sure the money could be directed towards a homeless shelter, but as in all large organisations (yes, that includes government), that generally has the effect that some of the other money is diverted somewhere else.

So I am afraid I don't really get your point. Are you saying that the trickle down effect from the church is comparable to the Mercy Corps in general? How come you don't give your monies to the LDS church then? (Sorry, that was uncalled for...)

In general, donations to a church would not be seen as charity over here, so just don't get it, I suppose.