They began strapping them to existing light poles here. I took a photo of one and it was gone a few days later. I didn't report it, it just vanished, which I noticed the next time I went for a walk. I want to know why they decided to put one up on my street, it feels like an intrusion.

Existing light poles are designed generally for very specific wind loading of only the lamp fixture on their ends, they're built to a very low cost spec to be cranked out in bulk. And to be a generally round or octagonal or whatever cross section that lets the wind flow around it in a worst-case 90 to 120 mph storm without any extra square or rectangular junk hanging off the side.

Adding appurtenances to one changes their wind loading and reliability. The engineers who signed off on some light pole designs might be unhappy to learn that multiple square feet of wind loading are being added after the fact.

The reason I know this is that in the telecom industry some (less experienced) people periodically try to use COTS light poles for some design that will hold just a few very small light duty sector antennas, or one or two 30cm size PTP microwave antennas in addition to the lamp fixture, as a "Hey I have this great idea to save some money" concept, and learn the hard way that the poles aren't rated or designed for it.