Save Electricity?????

You asked Why?

Because they're cheaper to install than a forced air or boiler system and if the inhabitant is responsible for the electric bill, the developer could care less what the ongoing cost is.

That's why consumers should always determine the TCO - Total Cost of Ownership - before making any substantial purchase

Not disagreeing, but there are some advantages to electric heat, one being the 'infinite zoning". Heat just one room instead of the whole house. Having said that, a traditional heating system, with portable electric heaters is probably a better solution. The lower-wattage parabolic radiants are the most practical/cheapest, I think.

Making this kind of statement without somekind of location qualifier makes no sense. Certainly here in the northeast usa you don't see new construction of townhomes, apartments or houses using electric heat. It might be happening in some locations, but I would bet it's relatively rare and that those areas have cheap electric for some special reasons.

They did this electric baseboard thing here in NY (L.I.) developments, Levittown-type deals. Was in fact a financial albatross for the owners.

While it is likely done because it is cheap and local codes allow it.

However there are times they are great ideas both from convince, effectiveness and economy.