In Spain that's a common misconception. The fact that wearing loafers with a suit has become accepted doesn't make it formal. It's just an accepted form of casualization. They're OK for everyday office wear but for a formal event or meeting of some sort you should still wear lace-ups. Bluchers are considered formal here, though (as long as there's not excessive brogueing)
Now there's a thing. I often wear black longwing brogued derbies as formal shoes and I think they look as much. I've never worked in Spain or much with Spaniards, so I didn't really notice whether they wear loafers. Italians Swiss, Greeks and Americans are the loaferists I've noticed over the years. And Arabs, but let's not go there.