You'd never know that from the way that Germans and Austrians will stand at a red crossing signal on a completely clear road

https://www.gesetze-im-internet.de/stvo_2013/__25.html "(3) Pedestrians must cross roadways quickly and by taking the shortest route perpendicular to the direction of travel, taking care to avoid vehicular traffic. If traffic density, speed, visibility, or traffic flow so requires, a roadway may only be crossed at intersections or junctions, at traffic lights within markings, at pedestrian crossing aids, or at pedestrian crossings (sign 293). When crossing the roadway at intersections or junctions, pedestrian crossings or markings at traffic lights must always be used."

Maybe there's no penalty, but a 6 lane road probably has traffic density/speed/flow enough to get to the "may only be crossed at intersections or junctions"

Downvoted, but true. If there is no crosswalk, you can cross. But, it might be dangerous or impossible as cars have right of way.