A rubber sole is the practical, all-weather finish: solid grip, real cushioning underfoot and a wearing surface that shrugs off the pavement.
It is thicker than leather and quieter than a lugged sole, which puts it in the useful middle — enough traction for a wet street, enough restraint to wear with tailoring.
It asks for nothing: no dry-day planning, no careful route around the puddle. Choose it for the pair that gets worn without thinking about it, the one that goes on in the morning whatever the forecast says and comes back looking the same.