Sometimes. Sometimes they create highways in the USA that have a huge gap in the middle so they can add more lanes in the future if needed. Those gaps can sometimes be repurposed for public transport. It's really just lobbyists that have pushed for cars since 1940 so the rich fucks can get richer by selling more cars. America has shit transportation so we can ensure the worst people in society get richer and richer.

Meanwhile Germany near Stuttgart Airport to Ulm:

I'd say it's ease of access and kind of makes sense to put it near the streets. Why destroy the environment more in unique places rather than within the street area which already has seen impacts of it through road traffic.

Though this railway is not 100% of the time near the highway.

This should make it feel more alien:

That station is in the middle of a 4 lane express way in both directions 90e and a 2 lane each way highway 90, which itself is wrapped on the outide with a 2 lane each way local arterial,