Smile I love the question because it is true people do sleep while traveling, but as for me I don't use to sleep while traveling.

Because have registered it in mind that sleeping doing traveling is not a bad habit to me, first I do think what if the driver take me to another place or have pass where am going to.

Or the driver is a kidnapper which I don't know, so even i was stress or I did not slept overnight if sleep until I get to where am going.