As streetlights are used in multiples, and are on for extended periods of time, any EMC issues are potentially worse than other random products.
Its not just an issue of multiples. The street light opposite me is fixed to the front wall of a house. The house wall is brick, so this light is basically in the same environment as any other appliance in the house. If you are in one of those town areas with front doors opening directly onto the pavement (sidewalk) all the street lights in the street are in basically the same position, whether the are attached to the front walls, or on poles very close to the front walls. Its a very strange idea that street lights present a low EMC profile, because they are distant objects.