Ah. That's helpful. US utility residential practice, for those outside the US, is that pole transformers take in 3 phase at a few KV, at 60Hz, and output 120/240 VAC single phase with a shared neutral. That's what most houses get, supplied over 3 wires, with a 3-wire single phase meter. Pole-mounted transformers usually serve about 7 houses or so.

Even in apartment buildings, each apartment has its own meter, almost always single phase.