>The local population is exceptionally socially progressive

...except for property taxes, zoning/housing/building, etc. e.g., I'd rephrase this as they're very progressive-brand-conscious regardless of the realities as everything turns into a bank branch.

Road & Track had a good writeup as to how Subaru became pretty entrenched in the area compared to other brands:

>With initial curiosity-driven demand dried up, and the Consumer Reports review echoing maliciously, U.S. Subaru sales ground to a halt.
>
>In 1971, Subaru of America embarked on an ambitious plan to outrun the bad review. As co-founder Bricklin told Automotive News in a rollicking interview earlier this year, "Somebody called me and said, 'Have you seen Consumer Reports?' I said, 'What's Consumer Reports?' [...] At the time, they had a circulation of half a million. So I thought, so what? Half a million people saw it, out of how many million in the United States?"
>
>So Subaru of America decided to focus on markets where Consumer Reports had less sway—as Automotive News puts it, "small towns where the reputation of the local dealer was more important than awareness of the brand he was selling." The American importer targeted rural regions far away from the big cities. Places like Vermont, Minnesota, Washington state, New Hampshire and western Pennsylvania—where hardworking people on a budget might be willing to try a relatively-unknown brand offering cheap, frugal transportation.

You then had the 1973 oil embargo and subaru's use of 4-wheel drive in a family car kind of sealing the deal.