The individual HD guys I come into contact with are usually quite nice and are often interested in my RE. Unfortunately I don't know any Harley riders on a personal level that would make it easy to ask questions like the following;
1. Do you realize how annoying really loud pipes are?
2. At your age do you really like or need to make a spectacle of yourself?
3. What is the real attraction to riding in large groups?
4. Is displaying "attitude" important to you?
The previous comment about HD riders being on another planet seems very apt.
Despite being puzzled and put off by HD culture I really admire some of the bikes, particularly the older XLCH models. I could see myself owning one albeit with real mufflers.
I think the issue here is that while there are plenty of motorcycle enthusiasts that enjoy riding Harley's, like the guys I know. There are just as many, probably more that see them as a "lifestyle accessory" that allows them to spend a couple of hours a week pretending to be someone they aren't. Since it's largely pretense they don't care how much they offend anyone because once they take off their costume they fade right back in to whatever they are in real life, and since riding probably isn't a long term thing for them they couldn't care less about the damage they do.
I'd also suggest that some percentage of the guys that gravitate towards HD's, a much greater percentage in fact than you'd find riding other brands are just going to be anti social A-holes, because they can be, and see riding an HD as a jingoistic way of reminding us that they're "tough guys."
Over the years HD has built some outstanding bikes, pre 70 Sportsters were among the best motorcycles you could buy, and anyone that thinks HD can't build a fast motorcycle when it wants to has never ridden an XR750. In dirt track or road race trim they were an outstandingly good motorcycle. Unfortunately the management at HD figured they'd get rich catering to a segment of the market that the other OEM's wanted little part of and were fairly successful at it for a number of years, and worse forced many of the other manufacturers to waste valuable resources on the cruiser market, which has no all but dried up.