I think you're right about the weather. Malaysia/Singapore has two seasons: a very hot dry season and a less hot rainy season. So in general, we can leave our shoes outdoors, or most houses are designed with double doors separated by a small foyer entryway, large enough for just a shoe closet.

We leave our shoes outside our apartment because we live in a six-unit complex; we probably wouldn't leave it open to the public (or viewable from the streets). When we lived in a house, we kept it like you did, just inside the door.