Wild.

Not in Indiana.

Seems to depend on the area. Traveling around the Midwest I basically never see them, but they’re huge in California for example

They are only in very congested high traffic areas. Near some large cities.

I wouldn’t say almost all. Less than half in my experience (mostly in TX and WA).

Live in the midwest and I’ve never seen one.

Minneapolis/St. Paul might have one I’ve just never encountered. They for sure have express lanes, which themselves are a feature I have only ever seen there and no where else in the surrounding region.