Why is it illegal to pass someone on the right on the highway in the US? In Canada if there’s a three lane highway which, in my case, isn’t very prominent, there’s really no law that enforces it, it’s more of a respect thing here on two lane highways both ways if someone is going slow in the left lane to go into the right but I’m just curious as to why it’s actually enforced in the US?
I think it's also about being predictable and consistent. Generally, slow traffic stays to the right and fast traffic stays to the left. Breaking convention increases the chance of surprises and accidents.
I think they probably have reasons for it but you pretty much just need to do it because it's the law in whatever state you're in and they'll ticket you if you don't