You're missing most of the point...BMW chose the wheels and tires on the i3 for whatever reason. I have no insight into the exact reason, but overall efficiency was one of the major design goals. They intentionally used plastic body panels to help avoid door dings, but those are caused by other people's actions, not your own. Dinging a wheel, or scraping the fender or bumper is normally in YOUR control, and the German mentality, at least from what I saw when I lived there, is that driving is a skill, and you don't hit things, so the other aspects of the design are more critical. The car can't protect you from everything.
BTW, I've been to LA lots of times...was there a few months ago. I didn't ding any wheels in the process, and I do live in a city, and do drive my i3 almost exclusively here while saving my ICE for longer trips or when I need more room. Boston traffic can be as congested as LA's, although not as big...still, you can have 8-lanes of stop and go traffic, and at least in LA, many of the streets are fairly straight...in Boston, many of them are paved cow paths from the 1600's and narrow, tree-lined. Nashua isn't all that far from Boston, and is in itself a nice city. Certainly not in the scale as LA, but then, there aren't many cities that are.
Lots of cars use wheels and tires that can be scraped on curbs...you are expected to be a good enough driver to avoid that from happening. The parallel parking routine in the car goes slow enough so if you're watching your mirrors, you can see a problem coming and stop. The manual describes when that system can have problems...you need to learn to detect them, since the car can't, or you can do it the old fashioned way, yourself!
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