Regionally dependent, typically based on the weather, terrain, and how populated the area is. In cold places with more than 16 feet to bedrock, you will typically have basements because they're cheaper to heat in the winter and cool in the summer. If the bedrock or the water table is close to the surface, basements are too expensive or impossible. If there is lots of space around you and it isn't too cold, you won't have basements because they cost more per square foot than building on the surface. If you're densely populated (and don't have the exclusion conditions listed above), you will likely have a basements because it costs less to have a second floor (above or below) than it does to buy more land.

In short, bungalows have basements where it's more cost-effective than having a bigger bungalow.

No.