A couple of Notes:

It is not legal in VA as stated by others.

It is not about getting to the front. It is far safer for motorcycles to filter between cars that are stopped than to remain in line. Bikes are often overlooked and rear-endings happen frequently. I personally know 3 people who have been rear ended on a bike in this manner. They all filter illegally now because fuck getting hit by cars when you are on a bike, save for the one who cant walk anymore because a 25yo was too busy looking at snapchat and not the road.

It reduces congestion - even small bikes (150CC) accelerate faster than most cars on the road are able. They are clear of traffic and no longer part of traffic by utilizing the empty space and quick acceleration.

Many cops also ride and are not likely to pull over a bike for filtering safely. The remainder are not likely to pursue a bike due to the assumption that the biker will run. It is not hard to lose the cops on a bike.