First of all, they do not go at high enough speeds to keep up with traffic. There is a minimum speed as well as a maximum speed on highways. And yes, you can get a ticket for going below the minimum speed. Also, to be highway legal in most of the US, a vehicle has to have over 100cc, or over 3 horsepower. Ebikes are typically in the 1 horsepower range. Consider also, that currently, ebikes are considered “bicycles” for road, sidewalk, and trail purposes in most of the US. Having been a motorcycle rider for over 45 years, as well as a mtn bike racer, I think this is wrong. However, being as that most consider them bicycles, they are definitely NOT allowed on highways.