Now here's a topic on which I have some knowledge and experience. I am a Land Surveyor by trade and have been involved in the industry of land development for about 23 years. The question that was asked was essentially whether there was a standard for placing street lights or not, and if there was, what is it? The answer is, as in most things, it depends.
There is a science to street light placement. It involves using charts and graphs that map out the illumination "footprint" of various types of street lights; considering local natural light patterns including how much sunlight is expected throughout the year; power consumption/availability issues; safety concerns; weather patterns; and a few other various local community considerations which all result in municipal standards for a given place.
I believe that Hank said he lives in Missoula, MT, which is not a very large city (by some standards, it is three time the population of my hometown in CA). And it has particular needs in relation to the lighting provided. But the point is that the city of Missoula will have a standard for the spacing and location of street lights to be installed on new housing developments. If I recall correctly, he said that the street lights in his particular neighborhood are just at the intersections. This leads me to believe he is either in a lower density, rural area or possibly in an older development. In both cases, the standards for street lighting would probably only require the lighting at intersections to address driving and pedestrian safety. Newer subdivisions, or developments with higher housing density (houses per acre) typically have a closer spacing and some specific placing requirements.
I've seen cities with a standard that requires them to alternate sides of the street. I've seen cities that only have a maximum distance between lights in their standards. And I've seen cities that only require lighting at intersections and and fire hydrants. And, of course, these standards change over time. A city may have a particular standard in place that meets what they think is the best practice for public lighting. But 10 or 20 years later, through new information acquired or new lighting technology or whatever, they may change their standard to require more or fewer lights. But the city isn't going to go back and retrofit the older parts of town with their new standards. That would require major disruption of the wiring and controlling equipment; not to mention all of the work in installing new lighting bases. So, the answer to this is that it depends upon where you are, and also when the part of the city was originally built.