Don't care much for your "willy nilly" comment, but the rest of it I'll take ... I was just surprised to see that they took a fixture on the driver's side and ran tubing all the way to the passenger side outside wall to accomplish what a check valve would but I understand your code perspective ...
Thankfully being an owner and not a manufacturer, I can do whatever pleases me and neat, clean, functional and effective pleases me ... but not at the sake of sound engineering logic of course ...
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