I've been stuck in traffic a couple times. One issue I've seen is automatic transmissions get too hot sitting like that since most people leave it in drive and let it sit and idle to keep the ac running. This causes heat to build up in the torque converter. So if your driving an automatic get a cooler and add it on, if yours already has the factory cooler get a larger one.
People try to make U turns in the middle of the road because it looks like its just grass, well its not. The center divider of a highway is designed to trap a vehicle to prevent you from driving across into the other lane going the wrong way and to allow water drainage. That center is grass on top of soft sand that you will sink into and people don't realize this so they get tired of waiting and cut into the center and get stuck, only a few true 4x4's can make it through most places, people with AWD cars, front wheel drive and 2 wheel drive are going to sink in.