It appears because it is used elsewhere, just at a much lower rate. Check the wiki. There are less than 800 uses compared to 8000 for denomination=mormon.

You did not change a church to a place of worship, you changed religion to latt, which is unrecognized. This caused your editor to identify it as a generic place of worship. Before you made this change, the editor called it a church, but that does not mean it is one.

All the nearby homes I checked are building=detached, not building=house house=detached, so I don't know what you're talking about there.