[hakfoo]

I know mechanics in particular can be quite chauvinistic.

In the US, for a very long time, you had to find an "import specialist" mechanic, even long past the point where Japanese brands had gone mainstream. Part of this might have been because of the availability of metric tools at the time; my family had a set of metric wrenches specifically because they had to do occasional light maintenance on their early Datsuns and Toyotas.

I can recall that the mechanic in my neighbourhood was decidedly unwilling to service a new Hyundai in the late '90s. He complained they were 'disposable'.

[imchillyb]

Mechanics are in business to be profitable.

Specialized items require specialized tools. Specialized tools, like all other tools, require maintenance and they change.

A shop dealing with domestic produced automobiles can significantly reduce profit-bleed by not servicing vehicles that require special tools, special diagnostics, special machines, etc.

It's simply a math equation. Do I serve enough of these vehicles daily/quarterly/yearly to make these expenditures profitable for me? The shops you're referring to answered no to that question.